bug fixing

Reviewed-on: #52

Backend/ERPCore.Tests/ERPCore.Tests.csproj

@@ -0,0 +1,26 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.EntityFrameworkCore.InMemory" Version="10.0.9" />
+    <PackageReference Include="coverlet.collector" Version="6.0.4" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.14.1" />
+    <PackageReference Include="xunit" Version="2.9.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="3.1.4" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\ERPCore\ERPCore.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Using Include="Xunit" />
+  </ItemGroup>
+
+</Project>

Backend/ERPCore.Tests/NotificationConfigServiceTests.cs

@@ -0,0 +1,152 @@
+using ERPCore.Domain.Entities;
+using ERPCore.Domain.Notifications;
+using ERPCore.Repositories;
+using ERPCore.Services;
+using ERPCore.System.Errors;
+using ERPCore.Tests.TestSupport;
+using Microsoft.EntityFrameworkCore;
+
+namespace ERPCore.Tests;
+
+public class NotificationConfigServiceTests
+{
+    [Fact]
+    public async Task GetAsync_MergesSavedValuesWithDiscoveredModules()
+    {
+        var dbName = Guid.NewGuid().ToString("N");
+        await using var db = NotificationConfigTestSupport.CreateContext(dbName);
+        await NotificationConfigTestSupport.SeedAsync(db, new[]
+        {
+            new NotificationConfigModule
+            {
+                ModuleKey = "sale.create",
+                EmailEnabled = true,
+                SmsEnabled = false,
+                InAppEnabled = true
+            }
+        });
+
+        var service = CreateService(db);
+
+        var result = await service.GetAsync();
+
+        Assert.Equal(7u, result.RowVersion);
+        Assert.Contains(result.Value.Modules, m => m.ModuleKey == "sale.create" && m.EmailEnabled && !m.SmsEnabled && m.InAppEnabled);
+        Assert.Contains(result.Value.Modules, m => m.ModuleKey == "grn.confirmed" && !m.EmailEnabled && !m.SmsEnabled && !m.InAppEnabled);
+    }
+
+    [Fact]
+    public async Task UpdateAsync_PersistsEmptyAndMultiChannelSelections()
+    {
+        var dbName = Guid.NewGuid().ToString("N");
+        await using var db = NotificationConfigTestSupport.CreateContext(dbName);
+        await NotificationConfigTestSupport.SeedAsync(db);
+
+        var service = CreateService(db);
+        var catalog = new NotificationModuleCatalog();
+        var request = new ERPCore.Dtos.Notifications.UpdateNotificationConfigRequest
+        {
+            Modules = catalog.GetAll().Select((module, index) => new ERPCore.Dtos.Notifications.UpdateNotificationModuleRequest
+            {
+                ModuleKey = module.Key,
+                EmailEnabled = index == 0,
+                SmsEnabled = index == 1,
+                InAppEnabled = index == 1
+            }).ToList()
+        };
+
+        var updated = await service.UpdateAsync(request, 7);
+
+        Assert.Equal(7u, updated.RowVersion);
+        Assert.Contains(updated.Value.Modules, m => m.ModuleKey == catalog.GetAll()[0].Key && m.EmailEnabled && !m.SmsEnabled && !m.InAppEnabled);
+        Assert.Contains(updated.Value.Modules, m => m.ModuleKey == catalog.GetAll()[1].Key && !m.EmailEnabled && m.SmsEnabled && m.InAppEnabled);
+
+        await using var verifyDb = NotificationConfigTestSupport.CreateContext(dbName);
+        var persisted = await verifyDb.NotificationConfigModules.AsNoTracking().ToListAsync();
+        Assert.Contains(persisted, m => m.ModuleKey == catalog.GetAll()[0].Key && m.EmailEnabled && !m.SmsEnabled && !m.InAppEnabled);
+        Assert.Contains(persisted, m => m.ModuleKey == catalog.GetAll()[1].Key && !m.EmailEnabled && m.SmsEnabled && m.InAppEnabled);
+    }
+
+    [Fact]
+    public async Task ResolveEnabledChannelsAsync_ReturnsEmptyWhenNothingEnabled()
+    {
+        var dbName = Guid.NewGuid().ToString("N");
+        await using var db = NotificationConfigTestSupport.CreateContext(dbName);
+        await NotificationConfigTestSupport.SeedAsync(db, new[]
+        {
+            new NotificationConfigModule
+            {
+                ModuleKey = "sale.create",
+                EmailEnabled = false,
+                SmsEnabled = false,
+                InAppEnabled = false
+            }
+        });
+
+        var service = CreateService(db);
+
+        var channels = await service.ResolveEnabledChannelsAsync("sale.create");
+
+        Assert.Empty(channels);
+    }
+
+    [Fact]
+    public async Task ResolveEnabledChannelsAsync_ReturnsMultipleChannels()
+    {
+        var dbName = Guid.NewGuid().ToString("N");
+        await using var db = NotificationConfigTestSupport.CreateContext(dbName);
+        await NotificationConfigTestSupport.SeedAsync(db, new[]
+        {
+            new NotificationConfigModule
+            {
+                ModuleKey = "sale.create",
+                EmailEnabled = true,
+                SmsEnabled = true,
+                InAppEnabled = false
+            }
+        });
+
+        var service = CreateService(db);
+
+        var channels = await service.ResolveEnabledChannelsAsync("sale.create");
+
+        Assert.Equal(new[] { NotificationChannel.Email, NotificationChannel.Sms }, channels);
+    }
+
+    [Fact]
+    public async Task UpdateAsync_MapsConcurrencyFailuresToDomainException()
+    {
+        var dbName = Guid.NewGuid().ToString("N");
+        await using var db = NotificationConfigTestSupport.CreateContext(dbName);
+        await NotificationConfigTestSupport.SeedAsync(db);
+
+        var service = CreateService(db, new ThrowingUnitOfWork());
+        var catalog = new NotificationModuleCatalog();
+        var request = new ERPCore.Dtos.Notifications.UpdateNotificationConfigRequest
+        {
+            Modules = catalog.GetAll().Select(module => new ERPCore.Dtos.Notifications.UpdateNotificationModuleRequest
+            {
+                ModuleKey = module.Key,
+                EmailEnabled = false,
+                SmsEnabled = false,
+                InAppEnabled = false
+            }).ToList()
+        };
+
+        var ex = await Assert.ThrowsAsync<DomainException>(() => service.UpdateAsync(request, 7));
+        Assert.Equal(ErrorCodes.ConcurrencyConflict, ex.Code);
+        Assert.Equal(412, ex.StatusCode);
+    }
+
+    private static NotificationConfigService CreateService(ERPCore.Infra.Persistence.ErpDbContext db, ERPCore.Infra.UoW.IUnitOfWork? uow = null)
+    {
+        var configRepo = new Repository<NotificationConfig>(db);
+        var moduleRepo = new Repository<NotificationConfigModule>(db);
+        return new NotificationConfigService(
+            configRepo,
+            moduleRepo,
+            new NotificationModuleCatalog(),
+            new TestCurrentUser(),
+            uow ?? new ERPCore.Infra.UoW.UnitOfWork(db));
+    }
+}

Backend/ERPCore.Tests/NotificationModuleCatalogTests.cs

@@ -0,0 +1,17 @@
+using ERPCore.Services;
+
+namespace ERPCore.Tests;
+
+public class NotificationModuleCatalogTests
+{
+    [Fact]
+    public void GetAll_ReturnsStableUniqueModuleKeys()
+    {
+        var catalog = new NotificationModuleCatalog();
+
+        Assert.NotEmpty(catalog.GetAll());
+        Assert.Contains(catalog.GetAll(), m => m.Key == "sale.create");
+        Assert.Contains(catalog.GetAll(), m => m.Key == "grn.confirmed");
+        Assert.Equal(catalog.GetAll().Count, catalog.GetAll().Select(m => m.Key).Distinct(StringComparer.OrdinalIgnoreCase).Count());
+    }
+}

Backend/ERPCore.Tests/TestSupport/NotificationConfigTestSupport.cs

@@ -0,0 +1,70 @@
+using ERPCore.Domain.Entities;
+using ERPCore.Infra.Auth;
+using ERPCore.Infra.Persistence;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Storage;
+
+namespace ERPCore.Tests.TestSupport;
+
+internal sealed class TestCurrentUser : ICurrentUser
+{
+    public string UserId => "system";
+    public int AuditUserId => User.SystemUserId;
+    public bool IsAuthenticated => false;
+}
+
+internal sealed class ThrowingUnitOfWork : ERPCore.Infra.UoW.IUnitOfWork
+{
+    public Task<int> SaveChangesAsync(CancellationToken ct = default)
+        => throw new DbUpdateConcurrencyException("Test concurrency conflict.");
+
+    public Task ExecuteInTransactionAsync(Func<CancellationToken, Task> action, CancellationToken ct = default)
+        => throw new NotSupportedException();
+
+    public Task<T> ExecuteInTransactionAsync<T>(Func<CancellationToken, Task<T>> action, CancellationToken ct = default)
+        => throw new NotSupportedException();
+}
+
+internal static class NotificationConfigTestSupport
+{
+    private static readonly InMemoryDatabaseRoot Root = new();
+
+    public static ErpDbContext CreateContext(string name)
+    {
+        var options = new DbContextOptionsBuilder<ErpDbContext>()
+            .UseInMemoryDatabase(name, Root)
+            .Options;
+
+        return new ErpDbContext(options, new TestCurrentUser());
+    }
+
+    public static async Task SeedAsync(ErpDbContext db, IEnumerable<NotificationConfigModule>? modules = null)
+    {
+        db.Users.Add(new User
+        {
+            UserId = User.SystemUserId,
+            Username = "system",
+            DisplayName = "System"
+        });
+
+        var config = new NotificationConfig
+        {
+            NotificationConfigId = NotificationConfig.SingletonId,
+            UpdatedBy = User.SystemUserId,
+            UpdatedAt = DateTime.UtcNow,
+            RowVersion = 7,
+        };
+
+        if (modules is not null)
+        {
+            foreach (var module in modules)
+            {
+                module.NotificationConfigId = NotificationConfig.SingletonId;
+                config.Modules.Add(module);
+            }
+        }
+
+        db.NotificationConfig.Add(config);
+        await db.SaveChangesAsync();
+    }
+}

Backend/ERPCore/Controllers/BranchConfigController.cs

@@ -0,0 +1,44 @@
+using ERPCore.Dtos.Config;
+using ERPCore.Services.Interfaces;
+using Microsoft.AspNetCore.Mvc;
+
+namespace ERPCore.Controllers;
+
+/// <summary>
+/// Branch configuration endpoints — the singleton toggle for whether this deployment
+/// requires a branch on Employee/Warehouse records at all.
+/// <para>
+/// <b>Authorization:</b> writes are admitted by the inherited ERP door policy only, same
+/// Phase-1 posture as <see cref="ProductConfigController"/> — any ERP-admitted user can
+/// flip this flag until per-endpoint RBAC lands.
+/// </para>
+/// </summary>
+[Route("api/v1/branch-config")]
+public sealed class BranchConfigController : ApiControllerBase
+{
+    private readonly IBranchConfigService _config;
+
+    public BranchConfigController(IBranchConfigService config) => _config = config;
+
+    [HttpGet]
+    [ProducesResponseType(typeof(BranchConfigDto), StatusCodes.Status200OK)]
+    public async Task<ActionResult<BranchConfigDto>> Get(CancellationToken ct)
+    {
+        var result = await _config.GetAsync(ct);
+        SetETag(result.RowVersion);
+        return Ok(result.Value);
+    }
+
+    [HttpPut]
+    [ProducesResponseType(typeof(BranchConfigDto), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status400BadRequest)]
+    [ProducesResponseType(StatusCodes.Status412PreconditionFailed)]
+    public async Task<ActionResult<BranchConfigDto>> Update(
+        [FromBody] UpdateBranchConfigRequest request, CancellationToken ct)
+    {
+        var expected = RequireIfMatch();
+        var result = await _config.UpdateAsync(request, expected, ct);
+        SetETag(result.RowVersion);
+        return Ok(result.Value);
+    }
+}

Backend/ERPCore/Controllers/BundleSalesController.cs

@@ -29,6 +29,14 @@ public sealed class BundleSalesController : ApiControllerBase
         return result is null ? NotFound() : Ok(result);
     }
 
+    [HttpPost("templates")]
+    [ProducesResponseType(typeof(BundleSaleTemplateDto), StatusCodes.Status201Created)]
+    public async Task<ActionResult<BundleSaleTemplateDto>> CreateTemplate([FromBody] CreateBundleSaleTemplateRequest request, CancellationToken ct)
+    {
+        var result = await _bundles.CreateTemplateAsync(request, ct);
+        return Created($"/api/v1/bundle-sales/templates/{result.BundleSaleTemplateId}", result);
+    }
+
     [HttpGet]
     [ProducesResponseType(typeof(PagedResponse<BundleSaleSummaryDto>), StatusCodes.Status200OK)]
     public async Task<ActionResult<PagedResponse<BundleSaleSummaryDto>>> List(

Backend/ERPCore/Controllers/DashboardController.cs

@@ -15,6 +15,6 @@ public sealed class DashboardController : ApiControllerBase
     /// <summary>Aggregate counts for stock, GRN, and procurement.</summary>
     [HttpGet("stats")]
     [ProducesResponseType(typeof(DashboardStatsDto), StatusCodes.Status200OK)]
-    public async Task<ActionResult<DashboardStatsDto>> GetStats(CancellationToken ct)
+    public async Task<ActionResult<DashboardStatsDto>> GetStats([FromQuery] int? branchId, CancellationToken ct)
-        => Ok(await _dashboard.GetStatsAsync(ct));
+        => Ok(await _dashboard.GetStatsAsync(branchId, ct));
 }

Backend/ERPCore/Controllers/GrnsController.cs

@@ -11,12 +11,10 @@ namespace ERPCore.Controllers;
 public sealed class GrnsController : ApiControllerBase
 {
     private readonly IGrnService _grns;
-    private readonly IGrnPaymentService _payments;
 
-    public GrnsController(IGrnService grns, IGrnPaymentService payments)
+    public GrnsController(IGrnService grns)
     {
         _grns = grns;
-        _payments = payments;
     }
 
     /// <summary>List GRNs, newest first.</summary>
@@ -24,8 +22,8 @@ public sealed class GrnsController : ApiControllerBase
     [ProducesResponseType(typeof(PagedResponse<GrnSummaryDto>), StatusCodes.Status200OK)]
     public async Task<ActionResult<PagedResponse<GrnSummaryDto>>> List(
         [FromQuery] PageQuery query, [FromQuery] GrnStatus? status, [FromQuery] int? poId,
-        [FromQuery] int? vendorId, [FromQuery] int? warehouseId, CancellationToken ct)
+        [FromQuery] int? vendorId, [FromQuery] int? warehouseId, [FromQuery] int? branchId, CancellationToken ct)
-        => Ok(await _grns.ListAsync(query, status, poId, vendorId, warehouseId, ct));
+        => Ok(await _grns.ListAsync(query, status, poId, vendorId, warehouseId, branchId, ct));
 
     [HttpGet("{grnId:int}")]
     [ProducesResponseType(typeof(GrnDto), StatusCodes.Status200OK)]
@@ -64,23 +62,4 @@ public sealed class GrnsController : ApiControllerBase
     public async Task<ActionResult<ReleaseLineResultDto>> Release(
         int grnId, int grnLineId, [FromBody] ReleaseLineRequest request, CancellationToken ct)
         => Ok(await _grns.ReleaseLineAsync(grnId, grnLineId, request.Action, ct));
-
-    /// <summary>Pay the vendor against this GRN's balance, in full or in installments; posts a real GL journal entry.</summary>
-    [HttpPost("{grnId:int}/payments")]
-    [ProducesResponseType(typeof(GrnPaymentDto), StatusCodes.Status201Created)]
-    [ProducesResponseType(StatusCodes.Status400BadRequest)]
-    [ProducesResponseType(StatusCodes.Status404NotFound)]
-    [ProducesResponseType(StatusCodes.Status409Conflict)]
-    public async Task<ActionResult<GrnPaymentDto>> Pay(int grnId, [FromBody] CreateGrnPaymentRequest request, CancellationToken ct)
-    {
-        var dto = await _payments.PayAsync(grnId, request, ct);
-        return Created($"/api/v1/grns/{grnId}/payments/{dto.GrnPaymentId}", dto);
-    }
-
-    /// <summary>Payment history for this GRN, newest first.</summary>
-    [HttpGet("{grnId:int}/payments")]
-    [ProducesResponseType(typeof(IReadOnlyList<GrnPaymentDto>), StatusCodes.Status200OK)]
-    [ProducesResponseType(StatusCodes.Status404NotFound)]
-    public async Task<ActionResult<IReadOnlyList<GrnPaymentDto>>> ListPayments(int grnId, CancellationToken ct)
-        => Ok(await _payments.ListAsync(grnId, ct));
 }

Backend/ERPCore/Controllers/NotificationConfigController.cs

@@ -0,0 +1,34 @@
+using ERPCore.Dtos.Notifications;
+using ERPCore.Services.Interfaces;
+using Microsoft.AspNetCore.Mvc;
+
+namespace ERPCore.Controllers;
+
+[Route("api/v1/notification-config")]
+public sealed class NotificationConfigController : ApiControllerBase
+{
+    private readonly INotificationConfigService _config;
+
+    public NotificationConfigController(INotificationConfigService config) => _config = config;
+
+    [HttpGet]
+    [ProducesResponseType(typeof(NotificationConfigDto), StatusCodes.Status200OK)]
+    public async Task<ActionResult<NotificationConfigDto>> Get(CancellationToken ct)
+    {
+        var result = await _config.GetAsync(ct);
+        SetETag(result.RowVersion);
+        return Ok(result.Value);
+    }
+
+    [HttpPut]
+    [ProducesResponseType(typeof(NotificationConfigDto), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status400BadRequest)]
+    [ProducesResponseType(StatusCodes.Status412PreconditionFailed)]
+    public async Task<ActionResult<NotificationConfigDto>> Update([FromBody] UpdateNotificationConfigRequest request, CancellationToken ct)
+    {
+        var expected = RequireIfMatch();
+        var result = await _config.UpdateAsync(request, expected, ct);
+        SetETag(result.RowVersion);
+        return Ok(result.Value);
+    }
+}

Backend/ERPCore/Controllers/ProductionRunsController.cs

@@ -24,6 +24,19 @@ public sealed class ProductionRunsController : ApiControllerBase
         CancellationToken ct)
         => Ok(await _runs.ListAsync(query, status, templateId, warehouseId, ct));
 
+    /// <summary>Produced-items report (FR-MFG-13): one row per run that has produced
+    /// something, plus a summary total over every filtered row.</summary>
+    [HttpGet("produced")]
+    [ProducesResponseType(typeof(ProducedListResponseDto), StatusCodes.Status200OK)]
+    public async Task<ActionResult<ProducedListResponseDto>> ListProduced(
+        [FromQuery] DateOnly? from,
+        [FromQuery] DateOnly? to,
+        [FromQuery] int? templateId,
+        [FromQuery] int? warehouseId,
+        [FromQuery] ProductionRunStatus? status,
+        CancellationToken ct)
+        => Ok(await _runs.ListProducedAsync(from, to, templateId, warehouseId, status, ct));
+
     [HttpGet("{runId:int}")]
     [ProducesResponseType(typeof(RunGraphDto), StatusCodes.Status200OK)]
     [ProducesResponseType(StatusCodes.Status404NotFound)]

Backend/ERPCore/Controllers/PurchaseInvoicesController.cs

@@ -0,0 +1,102 @@
+using ERPCore.Domain.Enums;
+using ERPCore.Dtos.Common;
+using ERPCore.Dtos.Grn;
+using ERPCore.Dtos.Procurement;
+using ERPCore.Services.Interfaces;
+using Microsoft.AspNetCore.Mvc;
+
+namespace ERPCore.Controllers;
+
+/// <summary>Purchase invoice endpoints — vendor invoices consolidating Confirmed GRNs.</summary>
+[Route("api/v1/purchase-invoices")]
+public sealed class PurchaseInvoicesController : ApiControllerBase
+{
+    private readonly IPurchaseInvoiceService _invoices;
+    private readonly IPurchaseInvoicePaymentService _payments;
+
+    public PurchaseInvoicesController(IPurchaseInvoiceService invoices, IPurchaseInvoicePaymentService payments)
+    {
+        _invoices = invoices;
+        _payments = payments;
+    }
+
+    [HttpGet]
+    [ProducesResponseType(typeof(PagedResponse<PurchaseInvoiceSummaryDto>), StatusCodes.Status200OK)]
+    public async Task<ActionResult<PagedResponse<PurchaseInvoiceSummaryDto>>> List(
+        [FromQuery] PageQuery query, [FromQuery] PurchaseInvoiceStatus? status, [FromQuery] int? vendorId, CancellationToken ct)
+        => Ok(await _invoices.ListAsync(query, status, vendorId, ct));
+
+    /// <summary>Confirmed, not-yet-invoiced GRNs for a vendor — candidates for a new/edited invoice.</summary>
+    [HttpGet("eligible-grns")]
+    [ProducesResponseType(typeof(IReadOnlyList<GrnEligibleForInvoiceDto>), StatusCodes.Status200OK)]
+    public async Task<ActionResult<IReadOnlyList<GrnEligibleForInvoiceDto>>> EligibleGrns([FromQuery] int vendorId, CancellationToken ct)
+        => Ok(await _invoices.ListEligibleGrnsAsync(vendorId, ct));
+
+    [HttpGet("{purchaseInvoiceId:int}")]
+    [ProducesResponseType(typeof(PurchaseInvoiceDto), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status404NotFound)]
+    public async Task<ActionResult<PurchaseInvoiceDto>> GetById(int purchaseInvoiceId, CancellationToken ct)
+    {
+        var result = await _invoices.GetAsync(purchaseInvoiceId, ct);
+        if (result is null) return NotFound();
+        SetETag(result.RowVersion);
+        return Ok(result.Value);
+    }
+
+    [HttpPost]
+    [ProducesResponseType(typeof(PurchaseInvoiceDto), StatusCodes.Status201Created)]
+    [ProducesResponseType(StatusCodes.Status409Conflict)]
+    [ProducesResponseType(StatusCodes.Status422UnprocessableEntity)]
+    public async Task<ActionResult<PurchaseInvoiceDto>> Create([FromBody] CreatePurchaseInvoiceRequest request, CancellationToken ct)
+    {
+        var result = await _invoices.CreateAsync(request, ct);
+        SetETag(result.RowVersion);
+        return Created($"/api/v1/purchase-invoices/{result.Value.PurchaseInvoiceId}", result.Value);
+    }
+
+    [HttpPut("{purchaseInvoiceId:int}")]
+    [ProducesResponseType(typeof(PurchaseInvoiceDto), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status404NotFound)]
+    [ProducesResponseType(StatusCodes.Status409Conflict)]
+    [ProducesResponseType(StatusCodes.Status412PreconditionFailed)]
+    public async Task<ActionResult<PurchaseInvoiceDto>> Update(int purchaseInvoiceId, [FromBody] UpdatePurchaseInvoiceRequest request, CancellationToken ct)
+    {
+        var expected = RequireIfMatch();
+        var result = await _invoices.UpdateAsync(purchaseInvoiceId, request, expected, ct);
+        SetETag(result.RowVersion);
+        return Ok(result.Value);
+    }
+
+    [HttpPost("{purchaseInvoiceId:int}/post")]
+    [ProducesResponseType(typeof(PurchaseInvoiceDto), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status404NotFound)]
+    [ProducesResponseType(StatusCodes.Status409Conflict)]
+    public async Task<ActionResult<PurchaseInvoiceDto>> Post(int purchaseInvoiceId, CancellationToken ct)
+        => Ok(await _invoices.PostAsync(purchaseInvoiceId, ct));
+
+    [HttpPost("{purchaseInvoiceId:int}/cancel")]
+    [ProducesResponseType(typeof(PurchaseInvoiceDto), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status404NotFound)]
+    [ProducesResponseType(StatusCodes.Status409Conflict)]
+    public async Task<ActionResult<PurchaseInvoiceDto>> Cancel(int purchaseInvoiceId, CancellationToken ct)
+        => Ok(await _invoices.CancelAsync(purchaseInvoiceId, ct));
+
+    /// <summary>Pay the vendor against this invoice's balance, in full or in installments; posts a real GL journal entry.</summary>
+    [HttpPost("{purchaseInvoiceId:int}/payments")]
+    [ProducesResponseType(typeof(PurchaseInvoicePaymentDto), StatusCodes.Status201Created)]
+    [ProducesResponseType(StatusCodes.Status400BadRequest)]
+    [ProducesResponseType(StatusCodes.Status404NotFound)]
+    [ProducesResponseType(StatusCodes.Status409Conflict)]
+    public async Task<ActionResult<PurchaseInvoicePaymentDto>> Pay(int purchaseInvoiceId, [FromBody] CreatePurchaseInvoicePaymentRequest request, CancellationToken ct)
+    {
+        var dto = await _payments.PayAsync(purchaseInvoiceId, request, ct);
+        return Created($"/api/v1/purchase-invoices/{purchaseInvoiceId}/payments/{dto.PurchaseInvoicePaymentId}", dto);
+    }
+
+    /// <summary>Payment history for this invoice, newest first.</summary>
+    [HttpGet("{purchaseInvoiceId:int}/payments")]
+    [ProducesResponseType(typeof(IReadOnlyList<PurchaseInvoicePaymentDto>), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status404NotFound)]
+    public async Task<ActionResult<IReadOnlyList<PurchaseInvoicePaymentDto>>> ListPayments(int purchaseInvoiceId, CancellationToken ct)
+        => Ok(await _payments.ListAsync(purchaseInvoiceId, ct));
+}

Backend/ERPCore/Controllers/SalesInvoicesController.cs

@@ -25,8 +25,9 @@ public sealed class SalesInvoicesController : ApiControllerBase
         [FromQuery] SalesInvoiceStatus? status,
         [FromQuery] int? customerId,
         [FromQuery] int? warehouseId,
+        [FromQuery] int? branchId,
         CancellationToken ct)
-        => Ok(await _invoices.ListAsync(query, status, customerId, warehouseId, ct));
+        => Ok(await _invoices.ListAsync(query, status, customerId, warehouseId, branchId, ct));
 
     [HttpGet("{salesInvoiceId:int}")]
     [ProducesResponseType(typeof(SalesInvoiceDto), StatusCodes.Status200OK)]

Backend/ERPCore/Controllers/StockAdjustmentsController.cs

@@ -17,8 +17,8 @@ public sealed class StockAdjustmentsController : ApiControllerBase
     [HttpGet]
     [ProducesResponseType(typeof(PagedResponse<AdjustmentSummaryDto>), StatusCodes.Status200OK)]
     public async Task<ActionResult<PagedResponse<AdjustmentSummaryDto>>> List(
-        [FromQuery] PageQuery query, [FromQuery] int? warehouseId, [FromQuery] int? reasonCodeId, CancellationToken ct)
+        [FromQuery] PageQuery query, [FromQuery] int? warehouseId, [FromQuery] int? branchId, [FromQuery] int? reasonCodeId, CancellationToken ct)
-        => Ok(await _adjustments.ListAsync(query, warehouseId, reasonCodeId, ct));
+        => Ok(await _adjustments.ListAsync(query, warehouseId, branchId, reasonCodeId, ct));
 
     /// <summary>Get one adjustment with its lines and the ledger entries it posted.</summary>
     [HttpGet("{adjustmentId:int}")]

Backend/ERPCore/Controllers/StockController.cs

@@ -28,8 +28,8 @@ public sealed class StockController : ApiControllerBase
     [HttpGet("on-hand/list")]
     [ProducesResponseType(typeof(PagedResponse<StockOnHandDto>), StatusCodes.Status200OK)]
     public async Task<ActionResult<PagedResponse<StockOnHandDto>>> OnHandList(
-        [FromQuery] int? itemId, [FromQuery] int? warehouseId, [FromQuery] PageQuery query, CancellationToken ct)
+        [FromQuery] int? itemId, [FromQuery] int? warehouseId, [FromQuery] int? branchId, [FromQuery] PageQuery query, CancellationToken ct)
-        => Ok(await _stock.GetOnHandListAsync(itemId, warehouseId, query, ct));
+        => Ok(await _stock.GetOnHandListAsync(itemId, warehouseId, branchId, query, ct));
 
     /// <summary>
     /// Immutable movement history. <c>sourceDocType</c>/<c>sourceDocId</c> answer "what did
@@ -39,11 +39,11 @@ public sealed class StockController : ApiControllerBase
     [HttpGet("ledger")]
     [ProducesResponseType(typeof(PagedResponse<StockLedgerRowDto>), StatusCodes.Status200OK)]
     public async Task<ActionResult<PagedResponse<StockLedgerRowDto>>> Ledger(
-        [FromQuery] int? itemId, [FromQuery] int? warehouseId,
+        [FromQuery] int? itemId, [FromQuery] int? warehouseId, [FromQuery] int? branchId,
         [FromQuery] DateOnly? from, [FromQuery] DateOnly? to,
         [FromQuery] string? sourceDocType, [FromQuery] int? sourceDocId,
         [FromQuery] PageQuery query, CancellationToken ct)
-        => Ok(await _stock.GetLedgerAsync(itemId, warehouseId, from, to, sourceDocType, sourceDocId, query, ct));
+        => Ok(await _stock.GetLedgerAsync(itemId, warehouseId, branchId, from, to, sourceDocType, sourceDocId, query, ct));
 
     [HttpGet("valuation")]
     [ProducesResponseType(typeof(StockValuationDto), StatusCodes.Status200OK)]
@@ -54,8 +54,8 @@ public sealed class StockController : ApiControllerBase
     [HttpGet("reorder-alerts")]
     [ProducesResponseType(typeof(PagedResponse<ReorderAlertDto>), StatusCodes.Status200OK)]
     public async Task<ActionResult<PagedResponse<ReorderAlertDto>>> ReorderAlerts(
-        [FromQuery] int? warehouseId, [FromQuery] PageQuery query, CancellationToken ct)
+        [FromQuery] int? warehouseId, [FromQuery] int? branchId, [FromQuery] PageQuery query, CancellationToken ct)
-        => Ok(await _reorder.GetAlertsAsync(warehouseId, query, ct));
+        => Ok(await _reorder.GetAlertsAsync(warehouseId, branchId, query, ct));
 
     /// <summary>Create a draft requisition for an item's suggested reorder quantity.</summary>
     [HttpPost("reorder-alerts/{itemId:int}/requisition")]

Backend/ERPCore/Controllers/StockCountsController.cs

@@ -18,8 +18,8 @@ public sealed class StockCountsController : ApiControllerBase
     [HttpGet]
     [ProducesResponseType(typeof(PagedResponse<CountSummaryDto>), StatusCodes.Status200OK)]
     public async Task<ActionResult<PagedResponse<CountSummaryDto>>> List(
-        [FromQuery] PageQuery query, [FromQuery] CountStatus? status, [FromQuery] int? warehouseId, CancellationToken ct)
+        [FromQuery] PageQuery query, [FromQuery] CountStatus? status, [FromQuery] int? warehouseId, [FromQuery] int? branchId, CancellationToken ct)
-        => Ok(await _counts.ListAsync(query, status, warehouseId, ct));
+        => Ok(await _counts.ListAsync(query, status, warehouseId, branchId, ct));
 
     [HttpGet("{countId:int}")]
     [ProducesResponseType(typeof(CountDto), StatusCodes.Status200OK)]

Backend/ERPCore/Controllers/StockTransfersController.cs

@@ -19,8 +19,8 @@ public sealed class StockTransfersController : ApiControllerBase
     [ProducesResponseType(typeof(PagedResponse<TransferSummaryDto>), StatusCodes.Status200OK)]
     public async Task<ActionResult<PagedResponse<TransferSummaryDto>>> List(
         [FromQuery] PageQuery query, [FromQuery] TransferStatus? status,
-        [FromQuery] int? srcWarehouseId, [FromQuery] int? destWarehouseId, CancellationToken ct)
+        [FromQuery] int? srcWarehouseId, [FromQuery] int? destWarehouseId, [FromQuery] int? branchId, CancellationToken ct)
-        => Ok(await _transfers.ListAsync(query, status, srcWarehouseId, destWarehouseId, ct));
+        => Ok(await _transfers.ListAsync(query, status, srcWarehouseId, destWarehouseId, branchId, ct));
 
     [HttpGet("{transferId:int}")]
     [ProducesResponseType(typeof(TransferDto), StatusCodes.Status200OK)]

Backend/ERPCore/Controllers/UsersController.cs

@@ -1,6 +1,7 @@
 using ERPCore.Dtos.Common;
 using ERPCore.Dtos.Hrm;
 using ERPCore.Dtos.Users;
+using ERPCore.Infra.Auth;
 using ERPCore.Services.Interfaces;
 using Microsoft.AspNetCore.Mvc;
 
@@ -15,11 +16,13 @@ public sealed class UsersController : ApiControllerBase
 {
     private readonly IUserManagementService _users;
     private readonly IEmployeeUserLinkService _links;
+    private readonly ICurrentUser _currentUser;
 
-    public UsersController(IUserManagementService users, IEmployeeUserLinkService links)
+    public UsersController(IUserManagementService users, IEmployeeUserLinkService links, ICurrentUser currentUser)
     {
         _users = users;
         _links = links;
+        _currentUser = currentUser;
     }
 
     /// <summary>Advisory forward-direction lookup: does a Staff record already exist with this email? (docs/12-BACKEND-HRM.md A.5)</summary>
@@ -53,7 +56,7 @@ public sealed class UsersController : ApiControllerBase
     [ProducesResponseType(StatusCodes.Status409Conflict)]
     public async Task<ActionResult<ManagedUserDto>> Create([FromBody] CreateUserRequest request, CancellationToken ct)
     {
-        var result = await _users.CreateAsync(request, ct);
+        var result = await _users.CreateAsync(request, _currentUser.AuditUserId, ct);
         return Created($"/api/v1/users/{result.UserId}", result);
     }
 

Backend/ERPCore/Domain/DocumentTypes.cs

@@ -10,6 +10,7 @@ public static class DocumentTypes
     public const string Rfq = "RFQ";
     public const string PurchaseOrder = "PO";
     public const string Grn = "GRN";
+    public const string PurchaseInvoice = "PINV";
     public const string Transfer = "TRF";
     public const string Adjustment = "ADJ";
     public const string Count = "CNT";
@@ -20,6 +21,7 @@ public static class DocumentTypes
     public const string SalesInvoice = "SI";
     public const string SalesSlip = "SSL";
     public const string BundleSale = "BND";
+    public const string BundleSaleTemplate = "TPL";
     public const string SalesReturn = "SRET";
 
     /// <summary>Cashier day-end close-out (Sales) — <c>DEND-2026-00001</c>.</summary>

Backend/ERPCore/Domain/Entities/Branch.cs

@@ -3,16 +3,19 @@ using ERPCore.Domain.Enums;
 namespace ERPCore.Domain.Entities;
 
 /// <summary>
-/// Branch/location master (FR-HR-MD-01) — multi-branch readiness. Referenced
+/// Branch/location master (FR-HR-MD-01) — multi-branch readiness. Required by
-/// optionally by <see cref="Employee.BranchId"/> and <see cref="PayrollRun.BranchId"/>.
+/// <see cref="Employee.BranchId"/>, optionally referenced by <see cref="PayrollRun.BranchId"/>.
 /// Deactivated, not deleted, when referenced. Model: docs/12-BACKEND-HRM.md Part C.1.
 /// </summary>
 public class Branch
 {
     public int BranchId { get; set; }
+
+    /// <summary>Server-generated on create ("BR-001", "BR-002", ...) — never accepted from the client.</summary>
     public string Code { get; set; } = string.Empty;
     public string Name { get; set; } = string.Empty;
     public string? Address { get; set; }
+    public string? PhoneNumber { get; set; }
     public EntityStatus Status { get; set; } = EntityStatus.Active;
 
     public DateTime CreatedAt { get; set; }

Backend/ERPCore/Domain/Entities/BranchConfig.cs

@@ -0,0 +1,27 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Branch configuration — a singleton row (single-tenant, docs/00-CORE §1) gating whether
+/// this deployment uses branches at all. When <see cref="BranchingEnabled"/> is off, the
+/// Employee/Warehouse create forms stop asking for a branch and every new record is
+/// silently assigned to the deployment's one default branch instead — schema-wise
+/// <c>Employee.BranchId</c>/<c>Warehouse.BranchId</c> stay <c>NOT NULL</c> either way, only
+/// the UI/UX requirement toggles. See <see cref="Services.BranchConfigService.ResolveBranchIdAsync"/>.
+/// </summary>
+public class BranchConfig
+{
+    /// <summary>Always 1 - the singleton row's id.</summary>
+    public const int SingletonId = 1;
+
+    public int ConfigId { get; set; }
+
+    public bool BranchingEnabled { get; set; } = true;
+
+    public DateTime? UpdatedAt { get; set; }
+
+    public int? UpdatedBy { get; set; }
+    public User? UpdatedByUser { get; set; }
+
+    /// <summary>PostgreSQL xmin-backed optimistic concurrency token (ETag source).</summary>
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/Employee.cs

@@ -50,7 +50,7 @@ public class Employee
     public Designation? Designation { get; set; }
     public int EmploymentTypeId { get; set; }
     public EmploymentType? EmploymentType { get; set; }
-    public int? BranchId { get; set; }
+    public int BranchId { get; set; }
     public Branch? Branch { get; set; }
     public int WorkShiftId { get; set; }
     public WorkShift? WorkShift { get; set; }

Backend/ERPCore/Domain/Entities/Grn.cs

@@ -22,6 +22,11 @@ public class Grn
     public int WarehouseId { get; set; }
     public Warehouse? Warehouse { get; set; }
 
+    /// <summary>Owning branch, set explicitly at creation — warehouses are shared across
+    /// branches, so branch scope can no longer be derived from <see cref="Warehouse"/>.</summary>
+    public int BranchId { get; set; }
+    public Branch? Branch { get; set; }
+
     public GrnStatus Status { get; set; } = GrnStatus.Draft;
 
     public int CreatedBy { get; set; }
@@ -34,14 +39,14 @@ public class Grn
     public string? GlJournalNo { get; set; }
     public DateTime? GlPostedAt { get; set; }
 
-    /// <summary>Sum of vendor payments made against this GRN's total payable (<see cref="GrnLine.LineTotal"/>).</summary>
+    /// <summary>The Purchase Invoice this GRN has been consolidated into, if any (null until
-    public decimal PaidAmount { get; set; }
+    /// invoiced). Vendor settlement is tracked on the invoice, not per-GRN — see
-    /// <summary>Total payable minus <see cref="PaidAmount"/>; installments accrue against this until it reaches zero.</summary>
+    /// <see cref="PurchaseInvoice"/>.</summary>
-    public decimal BalanceAmount { get; set; }
+    public int? PurchaseInvoiceId { get; set; }
+    public PurchaseInvoice? PurchaseInvoice { get; set; }
 
     /// <summary>PostgreSQL xmin-backed optimistic concurrency token.</summary>
     public uint RowVersion { get; set; }
 
     public ICollection<GrnLine> Lines { get; set; } = new List<GrnLine>();
-    public ICollection<GrnPayment> Payments { get; set; } = new List<GrnPayment>();
 }

Backend/ERPCore/Domain/Entities/Item.cs

@@ -44,11 +44,12 @@ public class Item
     public string? TaxClass { get; set; }
 
     /// <summary>
-    /// Optional fixed selling price used by Sales only. <c>null</c> means "use stock value"
+    /// Optional selling price range and flat price used by Sales only.
-    /// (the item is sold at its FIFO stock cost at sale time); a value is the fixed sale price.
+    /// <c>null</c> values mean the field is not set. These values never enter costing/GRN/FIFO.
-    /// Never enters costing/GRN/FIFO (docs/10 Part C.1, C.9).
     /// </summary>
-    public decimal? SalePrice { get; set; }
+    public decimal? SellingMinPrice { get; set; }
+    public decimal? SellingMaxPrice { get; set; }
+    public decimal? SellingFlatPrice { get; set; }
 
     /// <summary>
     /// How much one pack holds, as the user entered it — <c>500</c> with

Backend/ERPCore/Domain/Entities/NotificationConfig.cs

@@ -0,0 +1,19 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Notification configuration (new settings module) - singleton root row.
+/// </summary>
+public class NotificationConfig
+{
+    public const int SingletonId = 1;
+
+    public int NotificationConfigId { get; set; }
+
+    public DateTime? UpdatedAt { get; set; }
+    public int? UpdatedBy { get; set; }
+    public User? UpdatedByUser { get; set; }
+
+    public uint RowVersion { get; set; }
+
+    public ICollection<NotificationConfigModule> Modules { get; set; } = new List<NotificationConfigModule>();
+}

Backend/ERPCore/Domain/Entities/NotificationConfigModule.cs

@@ -0,0 +1,14 @@
+namespace ERPCore.Domain.Entities;
+
+public class NotificationConfigModule
+{
+    public int NotificationConfigModuleId { get; set; }
+
+    public int NotificationConfigId { get; set; }
+    public NotificationConfig? NotificationConfig { get; set; }
+
+    public string ModuleKey { get; set; } = string.Empty;
+    public bool EmailEnabled { get; set; }
+    public bool SmsEnabled { get; set; }
+    public bool InAppEnabled { get; set; }
+}

Backend/ERPCore/Domain/Entities/ProductConfig.cs

@@ -1,22 +1,24 @@
 namespace ERPCore.Domain.Entities;
 
 /// <summary>
-/// Product configuration (FR-MD-11) — a <b>singleton row</b> (single-tenant, docs/00-CORE §1)
+/// Product configuration (FR-MD-11) - a singleton row (single-tenant, docs/00-CORE §1)
 /// gating optional product master-data features.
 /// <para>
 /// <see cref="SubcategoriesEnabled"/> and <see cref="BrandsEnabled"/> are enforced
 /// server-side: an Item write carrying a subcategory/brand while the flag is off is
-/// rejected with <c>CONFIG_DISABLED</c>. <see cref="ItemTypesEnabled"/> is
+/// rejected with <c>CONFIG_DISABLED</c>. <see cref="ItemTypesEnabled"/> is advisory only
-/// <b>advisory only</b> — items carry no item-type reference (see <see cref="ItemType"/>),
+/// - items carry no item-type reference (see <see cref="ItemType"/>), so there is nothing
-/// so there is nothing on a write to reject; the frontend honours it by hiding the
+/// on a write to reject; the frontend honours it by hiding the variant builder.
-/// builder's type section. Reads are never gated, so existing data stays visible after a
+/// <see cref="SellingPricesEnabled"/>, <see cref="SerialNumbersEnabled"/>,
-/// flag is switched off.
+/// <see cref="BatchListsEnabled"/> and <see cref="WarrantyPeriodsEnabled"/> are enforced
+/// on item writes and drive the create/edit screens. Reads are never gated, so existing
+/// data stays visible after a flag is switched off.
 /// </para>
 /// Model: docs/10-BACKEND-PHASE1.md Part C.1.
 /// </summary>
 public class ProductConfig
 {
-    /// <summary>Always 1 — the singleton row's id.</summary>
+    /// <summary>Always 1 - the singleton row's id.</summary>
     public const int SingletonId = 1;
 
     public int ConfigId { get; set; }
@@ -24,6 +26,10 @@ public class ProductConfig
     public bool SubcategoriesEnabled { get; set; } = true;
     public bool BrandsEnabled { get; set; } = true;
     public bool ItemTypesEnabled { get; set; } = true;
+    public bool SellingPricesEnabled { get; set; } = true;
+    public bool SerialNumbersEnabled { get; set; } = true;
+    public bool BatchListsEnabled { get; set; } = true;
+    public bool WarrantyPeriodsEnabled { get; set; } = true;
 
     public DateTime? UpdatedAt { get; set; }
 

Backend/ERPCore/Domain/Entities/PurchaseInvoice.cs

@@ -0,0 +1,50 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Vendor invoice consolidating one or more Confirmed GRNs for the same vendor
+/// (each linked GRN becomes one <see cref="PurchaseInvoiceLine"/>, not re-itemized).
+/// Draft is editable (GRNs can be re-selected); Posted reclassifies the GRN clearing
+/// balance to Accounts Payable (see PurchaseInvoiceService.PostAsync); vendor payments
+/// are then recorded against this aggregate rather than against the individual GRNs.
+/// </summary>
+public class PurchaseInvoice
+{
+    public int PurchaseInvoiceId { get; set; }
+    public string DocNo { get; set; } = string.Empty;
+
+    public string VendorInvoiceNo { get; set; } = string.Empty;
+    public DateTime VendorInvoiceDate { get; set; }
+
+    public int VendorId { get; set; }
+    public Vendor? Vendor { get; set; }
+
+    public string VendorSnapshotName { get; set; } = string.Empty;
+    public string? VendorSnapshotTaxNo { get; set; }
+
+    public PurchaseInvoiceStatus Status { get; set; } = PurchaseInvoiceStatus.Draft;
+
+    public decimal Subtotal { get; set; }
+    public decimal VatTotal { get; set; }
+    public decimal GrandTotal { get; set; }
+    public decimal PaidAmount { get; set; }
+    public decimal BalanceAmount { get; set; }
+
+    /// <summary>Journal number of the AP-recognition GL journal entry posted when this
+    /// invoice is Posted (Debit GRN Clearing / Credit Accounts Payable) — see
+    /// PurchaseInvoiceService.PostAsync.</summary>
+    public string? GlJournalNo { get; set; }
+    public DateTime? GlPostedAt { get; set; }
+
+    public int CreatedBy { get; set; }
+    public User? Creator { get; set; }
+
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+
+    public uint RowVersion { get; set; }
+
+    public ICollection<PurchaseInvoiceLine> Lines { get; set; } = new List<PurchaseInvoiceLine>();
+    public ICollection<PurchaseInvoicePayment> Payments { get; set; } = new List<PurchaseInvoicePayment>();
+}

Backend/ERPCore/Domain/Entities/PurchaseInvoiceLine.cs

@@ -0,0 +1,21 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// One row per consolidated GRN on a <see cref="PurchaseInvoice"/> — a straight
+/// consolidation of that GRN's line totals, not a re-itemization (docs: Purchase
+/// Invoice consolidates GRNs, it does not re-enter item lines).
+/// </summary>
+public class PurchaseInvoiceLine
+{
+    public int PurchaseInvoiceLineId { get; set; }
+
+    public int PurchaseInvoiceId { get; set; }
+    public PurchaseInvoice? PurchaseInvoice { get; set; }
+
+    public int GrnId { get; set; }
+    public Grn? Grn { get; set; }
+
+    public decimal Subtotal { get; set; }
+    public decimal VatTotal { get; set; }
+    public decimal LineTotal { get; set; }
+}

Backend/ERPCore/Domain/Entities/PurchaseInvoicePayment.cs

@@ -1,16 +1,17 @@
 namespace ERPCore.Domain.Entities;
 
 /// <summary>
-/// A vendor payment made against a confirmed GRN's balance (installments allowed —
+/// A vendor payment made against a Posted purchase invoice's balance (installments
-/// see GrnPaymentService.PayAsync). Posts its own real GL journal entry (Debit GRN
+/// allowed — see PurchaseInvoicePaymentService.PayAsync). Posts its own real GL
-/// Clearing / Credit the selected bank-or-cash account) before being recorded here.
+/// journal entry (Debit Accounts Payable / Credit the selected bank-or-cash account)
+/// before being recorded here.
 /// </summary>
-public class GrnPayment
+public class PurchaseInvoicePayment
 {
-    public int GrnPaymentId { get; set; }
+    public int PurchaseInvoicePaymentId { get; set; }
 
-    public int GrnId { get; set; }
+    public int PurchaseInvoiceId { get; set; }
-    public Grn? Grn { get; set; }
+    public PurchaseInvoice? PurchaseInvoice { get; set; }
 
     public decimal Amount { get; set; }
     public DateTime PaymentDate { get; set; }

Backend/ERPCore/Domain/Entities/SalesInvoice.cs

@@ -17,6 +17,11 @@ public class SalesInvoice
     public int WarehouseId { get; set; }
     public Warehouse? Warehouse { get; set; }
 
+    /// <summary>Owning branch, set explicitly at creation — warehouses are shared across
+    /// branches, so branch scope can no longer be derived from <see cref="Warehouse"/>.</summary>
+    public int BranchId { get; set; }
+    public Branch? Branch { get; set; }
+
     public SalesInvoiceType InvoiceType { get; set; } = SalesInvoiceType.B2C;
     public SalesInvoiceStatus Status { get; set; } = SalesInvoiceStatus.Draft;
 

Backend/ERPCore/Domain/Entities/SalesInvoicePayment.cs

@@ -4,7 +4,7 @@ namespace ERPCore.Domain.Entities;
 /// A customer payment made against a Posted sales invoice's balance (installments
 /// allowed — see SalesInvoicePaymentService.PayAsync). Posts its own real GL journal
 /// entry (Debit the selected bank-or-cash account / Credit Accounts Receivable) before
-/// being recorded here — the mirror image of <see cref="GrnPayment"/>.
+/// being recorded here — the mirror image of <see cref="PurchaseInvoicePayment"/>.
 /// </summary>
 public class SalesInvoicePayment
 {

Backend/ERPCore/Domain/Entities/StockAdjustment.cs

@@ -19,6 +19,11 @@ public class StockAdjustment
     public int ReasonCodeId { get; set; }
     public ReasonCode? ReasonCode { get; set; }
 
+    /// <summary>Owning branch, set explicitly at creation — warehouses are shared across
+    /// branches, so branch scope can no longer be derived from <see cref="Warehouse"/>.</summary>
+    public int BranchId { get; set; }
+    public Branch? Branch { get; set; }
+
     public AdjustmentStatus Status { get; set; } = AdjustmentStatus.Posted;
 
     public int CreatedBy { get; set; }

Backend/ERPCore/Domain/Entities/StockCount.cs

@@ -16,6 +16,11 @@ public class StockCount
     public int WarehouseId { get; set; }
     public Warehouse? Warehouse { get; set; }
 
+    /// <summary>Owning branch, set explicitly at creation — warehouses are shared across
+    /// branches, so branch scope can no longer be derived from <see cref="Warehouse"/>.</summary>
+    public int BranchId { get; set; }
+    public Branch? Branch { get; set; }
+
     public CountType CountType { get; set; }
     public CountStatus Status { get; set; } = CountStatus.Draft;
 

Backend/ERPCore/Domain/Entities/StockTransfer.cs

@@ -19,6 +19,11 @@ public class StockTransfer
     public int DestWarehouseId { get; set; }
     public Warehouse? DestWarehouse { get; set; }
 
+    /// <summary>Owning branch, set explicitly at creation — warehouses are shared across
+    /// branches, so branch scope can no longer be derived from src/dest warehouse.</summary>
+    public int BranchId { get; set; }
+    public Branch? Branch { get; set; }
+
     public TransferStatus Status { get; set; } = TransferStatus.Draft;
 
     public int CreatedBy { get; set; }

Backend/ERPCore/Domain/Entities/Warehouse.cs

@@ -9,6 +9,8 @@ public class Warehouse
     public int WarehouseId { get; set; }
     public string Code { get; set; } = string.Empty;
     public string Name { get; set; } = string.Empty;
+    public int BranchId { get; set; }
+    public Branch? Branch { get; set; }
 
     public ICollection<Bin> Bins { get; set; } = new List<Bin>();
 }

Backend/ERPCore/Domain/Enums/PurchaseInvoiceStatus.cs

@@ -0,0 +1,8 @@
+namespace ERPCore.Domain.Enums;
+
+public enum PurchaseInvoiceStatus
+{
+    Draft,
+    Posted,
+    Cancelled
+}

Backend/ERPCore/Domain/Notifications/Modules/NotificationModules.cs

@@ -0,0 +1,34 @@
+namespace ERPCore.Domain.Notifications.Modules;
+
+[NotificationModule("sale.create", "Sale Created", "Raised when a sales document is created.", 10)]
+public sealed class SaleCreateNotificationModule;
+
+[NotificationModule("sale.posted", "Sale Posted", "Raised when a sales document is posted.", 20)]
+public sealed class SalePostedNotificationModule;
+
+[NotificationModule("grn.created", "GRN Created", "Raised when a goods receipt note is created.", 30)]
+public sealed class GrnCreatedNotificationModule;
+
+[NotificationModule("grn.confirmed", "GRN Confirmed", "Raised when a goods receipt note is confirmed.", 40)]
+public sealed class GrnConfirmedNotificationModule;
+
+[NotificationModule("purchase.order.created", "Purchase Order Created", "Raised when a purchase order is created.", 50)]
+public sealed class PurchaseOrderCreatedNotificationModule;
+
+[NotificationModule("purchase.order.approved", "Purchase Order Approved", "Raised when a purchase order is approved.", 60)]
+public sealed class PurchaseOrderApprovedNotificationModule;
+
+[NotificationModule("purchase.return.created", "Purchase Return Created", "Raised when a purchase return is created.", 70)]
+public sealed class PurchaseReturnCreatedNotificationModule;
+
+[NotificationModule("stock.adjustment.created", "Stock Adjustment Created", "Raised when a stock adjustment is created.", 80)]
+public sealed class StockAdjustmentCreatedNotificationModule;
+
+[NotificationModule("stock.transfer.created", "Stock Transfer Created", "Raised when a stock transfer is created.", 90)]
+public sealed class StockTransferCreatedNotificationModule;
+
+[NotificationModule("item.created", "Item Created", "Raised when an item master record is created.", 100)]
+public sealed class ItemCreatedNotificationModule;
+
+[NotificationModule("item.updated", "Item Updated", "Raised when an item master record is updated.", 110)]
+public sealed class ItemUpdatedNotificationModule;

Backend/ERPCore/Domain/Notifications/NotificationChannel.cs

@@ -0,0 +1,8 @@
+namespace ERPCore.Domain.Notifications;
+
+public enum NotificationChannel
+{
+    Email,
+    Sms,
+    InApp
+}

Backend/ERPCore/Domain/Notifications/NotificationModuleAttribute.cs

@@ -0,0 +1,18 @@
+namespace ERPCore.Domain.Notifications;
+
+[AttributeUsage(AttributeTargets.Class, AllowMultiple = false, Inherited = false)]
+public sealed class NotificationModuleAttribute : Attribute
+{
+    public string Key { get; }
+    public string Label { get; }
+    public string Description { get; }
+    public int SortOrder { get; }
+
+    public NotificationModuleAttribute(string key, string label, string description, int sortOrder)
+    {
+        Key = key;
+        Label = label;
+        Description = description;
+        SortOrder = sortOrder;
+    }
+}

Backend/ERPCore/Domain/Notifications/NotificationModuleDefinition.cs

@@ -0,0 +1,7 @@
+namespace ERPCore.Domain.Notifications;
+
+public sealed record NotificationModuleDefinition(
+    string Key,
+    string Label,
+    string Description,
+    int SortOrder);

Backend/ERPCore/Dtos/Config/BranchConfigDtos.cs

@@ -0,0 +1,20 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace ERPCore.Dtos.Config;
+
+/// <summary>Branch configuration resource — the singleton toggle for whether this deployment
+/// requires a branch on Employee/Warehouse records at all.</summary>
+public sealed record BranchConfigDto(bool BranchingEnabled, DateTime? UpdatedAt, int? UpdatedBy);
+
+/// <summary>
+/// Full replacement of the flag. <c>UpdatedBy</c> is derived from the token, never posted.
+/// <para>
+/// <see cref="BranchingEnabled"/> is <see cref="bool"/>? deliberately: <c>[Required]</c> on a
+/// non-nullable bool is a no-op, so an omitted flag would otherwise silently bind to
+/// <c>false</c>. Nullable makes the requirement actually bind — an omitted flag is a 400.
+/// </para>
+/// </summary>
+public sealed class UpdateBranchConfigRequest
+{
+    [Required] public bool? BranchingEnabled { get; set; }
+}

Backend/ERPCore/Dtos/Config/ProductConfigDtos.cs

@@ -4,10 +4,14 @@ namespace ERPCore.Dtos.Config;
 
 /// <summary>
 /// Product configuration resource (docs/11-BACKEND-PHASE1.md §2.8). Singleton.
-/// <see cref="ItemTypesEnabled"/> is advisory (frontend-honoured) — see the entity docs.
+/// <see cref="ItemTypesEnabled"/> is advisory (frontend-honoured) - see the entity docs.
+/// <see cref="SellingPricesEnabled"/>, <see cref="SerialNumbersEnabled"/>,
+/// <see cref="BatchListsEnabled"/> and <see cref="WarrantyPeriodsEnabled"/> are enforced
+/// when items are written.
 /// </summary>
 public sealed record ProductConfigDto(
     bool SubcategoriesEnabled, bool BrandsEnabled, bool ItemTypesEnabled,
+    bool SellingPricesEnabled, bool SerialNumbersEnabled, bool BatchListsEnabled, bool WarrantyPeriodsEnabled,
     DateTime? UpdatedAt, int? UpdatedBy);
 
 /// <summary>
@@ -15,8 +19,8 @@ public sealed record ProductConfigDto(
 /// <para>
 /// The flags are <see cref="bool"/>? deliberately: <c>[Required]</c> on a non-nullable bool
 /// is a no-op (it always has a value), so a body of <c>{}</c> would bind every flag to
-/// <c>false</c> and silently switch all three features off. Nullable makes the requirement
+/// <c>false</c> and silently switch everything off. Nullable makes the requirement actually
-/// actually bind — an omitted flag is a 400, not an accidental disable.
+/// bind - an omitted flag is a 400, not an accidental disable.
 /// </para>
 /// </summary>
 public sealed class UpdateProductConfigRequest
@@ -24,4 +28,8 @@ public sealed class UpdateProductConfigRequest
     [Required] public bool? SubcategoriesEnabled { get; set; }
     [Required] public bool? BrandsEnabled { get; set; }
     [Required] public bool? ItemTypesEnabled { get; set; }
+    [Required] public bool? SellingPricesEnabled { get; set; }
+    [Required] public bool? SerialNumbersEnabled { get; set; }
+    [Required] public bool? BatchListsEnabled { get; set; }
+    [Required] public bool? WarrantyPeriodsEnabled { get; set; }
 }

Backend/ERPCore/Dtos/Grn/GrnDtos.cs

@@ -15,36 +15,30 @@ public sealed record GrnLineDto(
     HoldStatus HoldStatus, int? BatchId, IReadOnlyList<GrnLineWarrantyNumberDto> WarrantyNumbers);
 
 public sealed record GrnDto(
-    int GrnId, string DocNo, int? PoId, int VendorId, int WarehouseId, GrnStatus Status,
+    int GrnId, string DocNo, int? PoId, int VendorId, int WarehouseId, int BranchId, GrnStatus Status,
     int CreatedBy, DateTime CreatedAt, DateTime? PostedAt, string? GlJournalNo,
-    decimal PaidAmount, decimal BalanceAmount, IReadOnlyList<GrnLineDto> Lines);
+    int? PurchaseInvoiceId, string? PurchaseInvoiceNo, IReadOnlyList<GrnLineDto> Lines);
 
 /// <summary>Row shape for <c>GET /grns</c> — line count instead of the lines themselves.</summary>
 public sealed record GrnSummaryDto(
-    int GrnId, string DocNo, int? PoId, int VendorId, int WarehouseId, GrnStatus Status,
+    int GrnId, string DocNo, int? PoId, int VendorId, int WarehouseId, int BranchId, GrnStatus Status,
     int CreatedBy, DateTime CreatedAt, DateTime? PostedAt, int LineCount,
-    decimal PaidAmount, decimal BalanceAmount);
+    int? PurchaseInvoiceId, string? PurchaseInvoiceNo);
 
 public sealed record CreatedLayerDto(
     int LayerId, int ItemId, int WarehouseId, int? BatchId,
     decimal QtyReceived, decimal QtyRemaining, decimal UnitCost, DateTime ReceiptDate);
 
 public sealed record GrnConfirmResultDto(
-    int GrnId, GrnStatus Status, DateTime PostedAt, string GlJournalNo, decimal BalanceAmount,
+    int GrnId, GrnStatus Status, DateTime PostedAt, string GlJournalNo,
     IReadOnlyList<CreatedLayerDto> CreatedLayers, IReadOnlyList<int> LedgerRefs, PurchaseOrderStatus? PoStatus);
 
 public sealed record ReleaseLineResultDto(int GrnLineId, HoldStatus HoldStatus);
 
-public sealed record GrnPaymentDto(
+/// <summary>A Confirmed, not-yet-invoiced GRN eligible to be consolidated onto a Purchase Invoice.</summary>
-    int GrnPaymentId, int GrnId, decimal Amount, DateTime PaymentDate,
+public sealed record GrnEligibleForInvoiceDto(
-    long GlBankAccountId, string BankAccountName, string? Reference, string? GlJournalNo, DateTime CreatedAt);
+    int GrnId, string DocNo, DateTime PostedAt, int WarehouseId,
-
+    int LineCount, decimal Subtotal, decimal VatTotal, decimal GrandTotal);
-public sealed class CreateGrnPaymentRequest
-{
-    [Range(0.01, double.MaxValue)] public decimal Amount { get; set; }
-    [Required] public long GlBankAccountId { get; set; }
-    [StringLength(100)] public string? Reference { get; set; }
-}
 
 // Requests ----------------------------------------------------------------------
 
@@ -87,6 +81,9 @@ public sealed class CreateGrnRequest
     /// <summary>Required for a direct receipt (no PO); ignored otherwise (vendor derives from the PO).</summary>
     public int? VendorId { get; set; }
     [Required] public int WarehouseId { get; set; }
+    /// <summary>Owning branch for this GRN — warehouses are shared, so this is what actually
+    /// scopes the document (resolved via IBranchConfigService; required when branching is enabled).</summary>
+    [Required] public int BranchId { get; set; }
     [Required, MinLength(1)] public List<CreateGrnLineInput> Lines { get; set; } = new();
 }
 

Backend/ERPCore/Dtos/Hrm/EmployeeDtos.cs

@@ -6,7 +6,7 @@ namespace ERPCore.Dtos.Hrm;
 public sealed record EmployeeListItemDto(
     int EmployeeId, string EmployeeCode, string FullName, string? Email,
     int DepartmentId, string? DepartmentName, int DesignationId, string? DesignationName,
-    int EmploymentTypeId, string? EmploymentTypeName, int? BranchId, string? BranchName,
+    int EmploymentTypeId, string? EmploymentTypeName, int BranchId, string? BranchName,
     EmployeeStatus Status, bool HasUserLink, DateTime HireDate);
 
 public sealed record EmployeeDetailDto(
@@ -16,7 +16,7 @@ public sealed record EmployeeDetailDto(
     string? City, string? PostalCode, string? Country,
     string? EmergencyContactName, string? EmergencyContactRelationship, string? EmergencyContactPhone,
     DateTime HireDate, DateTime? ConfirmationDate, DateTime? LastWorkingDate,
-    int DepartmentId, int DesignationId, int EmploymentTypeId, int? BranchId, int WorkShiftId,
+    int DepartmentId, int DesignationId, int EmploymentTypeId, int BranchId, int WorkShiftId,
     int? ReportingManagerId, string? EpfNumber, string? EtfNumber, string? TaxIdentificationNumber,
     int? UserId, EmployeeStatus Status, DateTime CreatedAt, DateTime? UpdatedAt);
 
@@ -45,7 +45,7 @@ public sealed class CreateEmployeeRequest
     [Required] public int DepartmentId { get; set; }
     [Required] public int DesignationId { get; set; }
     [Required] public int EmploymentTypeId { get; set; }
-    public int? BranchId { get; set; }
+    [Required] public int BranchId { get; set; }
     [Required] public int WorkShiftId { get; set; }
     public int? ReportingManagerId { get; set; }
 
@@ -82,7 +82,7 @@ public sealed class UpdateEmployeeRequest
     [Required] public int DepartmentId { get; set; }
     [Required] public int DesignationId { get; set; }
     [Required] public int EmploymentTypeId { get; set; }
-    public int? BranchId { get; set; }
+    [Required] public int BranchId { get; set; }
     [Required] public int WorkShiftId { get; set; }
     public int? ReportingManagerId { get; set; }
 

Backend/ERPCore/Dtos/Hrm/OrgMasterDtos.cs

@@ -7,20 +7,22 @@ namespace ERPCore.Dtos.Hrm;
 // ids, timestamps) excluded from create/update requests (02-SECURITY B.6/C.1).
 
 public sealed record BranchDto(
-    int BranchId, string Code, string Name, string? Address, EntityStatus Status,
+    int BranchId, string Code, string Name, string? Address, string? PhoneNumber, EntityStatus Status,
     DateTime CreatedAt, DateTime? UpdatedAt);
 
+// Code is server-generated (BranchService.GenerateCodeAsync) — never accepted from the client.
 public sealed class CreateBranchRequest
 {
-    [Required, StringLength(20)] public string Code { get; set; } = string.Empty;
     [Required, StringLength(200)] public string Name { get; set; } = string.Empty;
     [StringLength(500)] public string? Address { get; set; }
+    [StringLength(30)] public string? PhoneNumber { get; set; }
 }
 
 public sealed class UpdateBranchRequest
 {
     [Required, StringLength(200)] public string Name { get; set; } = string.Empty;
     [StringLength(500)] public string? Address { get; set; }
+    [StringLength(30)] public string? PhoneNumber { get; set; }
 }
 
 public sealed record DepartmentDto(

Backend/ERPCore/Dtos/Items/ItemDtos.cs

@@ -10,7 +10,7 @@ public sealed record ItemListItemDto(
     int ItemId, string Sku, string Name, int CategoryId, int? SubCategoryId, int? BrandId,
     int BaseUomId, int? DefaultVendorId, StockNature StockNature, TrackingMode TrackingMode,
     Warranty Warranty, int? WarrantyPeriodMonths,
-    string? TaxClass, decimal? SalePrice,
+    string? TaxClass, decimal? SellingMinPrice, decimal? SellingMaxPrice, decimal? SellingFlatPrice,
     decimal? ContentQty, MeasureUnit? ContentUnit,
     decimal? ContentBaseQty, MeasureUnit? ContentBaseUnit,
     EntityStatus Status);
@@ -31,7 +31,7 @@ public sealed record ItemDetailDto(
     int? SubCategoryId, int? BrandId, int BaseUomId, int? DefaultVendorId,
     StockNature StockNature, TrackingMode TrackingMode,
     Warranty Warranty, int? WarrantyPeriodMonths,
-    string? TaxClass, decimal? SalePrice,
+    string? TaxClass, decimal? SellingMinPrice, decimal? SellingMaxPrice, decimal? SellingFlatPrice,
     decimal? ContentQty, MeasureUnit? ContentUnit,
     decimal? ContentBaseQty, MeasureUnit? ContentBaseUnit,
     EntityStatus Status, IReadOnlyList<ItemReorderDto> Reorder,
@@ -66,7 +66,9 @@ public sealed class CreateItemRequest
     public int? WarrantyPeriodMonths { get; set; }
     [StringLength(20)] public string? TaxClass { get; set; }
     /// <summary>Optional fixed sale price (Sales only). Null ⇒ sell at stock/FIFO value.</summary>
-    [Range(0, double.MaxValue)] public decimal? SalePrice { get; set; }
+    [Range(0, double.MaxValue)] public decimal? SellingMinPrice { get; set; }
+    [Range(0, double.MaxValue)] public decimal? SellingMaxPrice { get; set; }
+    [Range(0, double.MaxValue)] public decimal? SellingFlatPrice { get; set; }
 
     /// <summary>
     /// How much one pack holds. Supply with <see cref="ContentUnit"/> or leave both null
@@ -96,7 +98,9 @@ public sealed class UpdateItemRequest
     public int? WarrantyPeriodMonths { get; set; }
     [StringLength(20)] public string? TaxClass { get; set; }
     /// <summary>Optional fixed sale price (Sales only). Null ⇒ sell at stock/FIFO value.</summary>
-    [Range(0, double.MaxValue)] public decimal? SalePrice { get; set; }
+    [Range(0, double.MaxValue)] public decimal? SellingMinPrice { get; set; }
+    [Range(0, double.MaxValue)] public decimal? SellingMaxPrice { get; set; }
+    [Range(0, double.MaxValue)] public decimal? SellingFlatPrice { get; set; }
 
     /// <summary>
     /// How much one pack holds. Supply with <see cref="ContentUnit"/> or leave both null

Backend/ERPCore/Dtos/Notifications/NotificationConfigDtos.cs

@@ -0,0 +1,29 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace ERPCore.Dtos.Notifications;
+
+public sealed record NotificationModuleConfigDto(
+    string ModuleKey,
+    string Label,
+    string Description,
+    bool EmailEnabled,
+    bool SmsEnabled,
+    bool InAppEnabled);
+
+public sealed record NotificationConfigDto(
+    IReadOnlyList<NotificationModuleConfigDto> Modules,
+    DateTime? UpdatedAt,
+    int? UpdatedBy);
+
+public sealed class UpdateNotificationModuleRequest
+{
+    [Required, StringLength(100)] public string ModuleKey { get; set; } = string.Empty;
+    [Required] public bool? EmailEnabled { get; set; }
+    [Required] public bool? SmsEnabled { get; set; }
+    [Required] public bool? InAppEnabled { get; set; }
+}
+
+public sealed class UpdateNotificationConfigRequest
+{
+    [Required, MinLength(0)] public List<UpdateNotificationModuleRequest> Modules { get; set; } = new();
+}

Backend/ERPCore/Dtos/Procurement/PurchaseInvoiceDtos.cs

@@ -0,0 +1,50 @@
+using System.ComponentModel.DataAnnotations;
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Dtos.Procurement;
+
+public sealed record PurchaseInvoiceLineDto(
+    int PurchaseInvoiceLineId, int GrnId, string GrnDocNo, DateTime GrnPostedAt,
+    decimal Subtotal, decimal VatTotal, decimal LineTotal);
+
+public sealed record PurchaseInvoiceTotalsDto(
+    decimal Subtotal, decimal VatTotal, decimal GrandTotal, decimal PaidAmount, decimal BalanceAmount);
+
+public sealed record PurchaseInvoiceDto(
+    int PurchaseInvoiceId, string DocNo, string VendorInvoiceNo, DateTime VendorInvoiceDate,
+    int VendorId, string VendorSnapshotName, string? VendorSnapshotTaxNo,
+    PurchaseInvoiceStatus Status, int GrnCount, int CreatedBy, DateTime CreatedAt, DateTime? UpdatedAt,
+    string? GlJournalNo, DateTime? GlPostedAt,
+    PurchaseInvoiceTotalsDto Totals, IReadOnlyList<PurchaseInvoiceLineDto> Lines);
+
+public sealed record PurchaseInvoiceSummaryDto(
+    int PurchaseInvoiceId, string DocNo, string VendorInvoiceNo, DateTime VendorInvoiceDate,
+    int VendorId, string VendorSnapshotName, PurchaseInvoiceStatus Status, int GrnCount,
+    PurchaseInvoiceTotalsDto Totals, DateTime CreatedAt, string? GlJournalNo);
+
+public sealed record PurchaseInvoicePaymentDto(
+    int PurchaseInvoicePaymentId, int PurchaseInvoiceId, decimal Amount, DateTime PaymentDate,
+    long GlBankAccountId, string BankAccountName, string? Reference, string? GlJournalNo, DateTime CreatedAt);
+
+public sealed class CreatePurchaseInvoicePaymentRequest
+{
+    [Range(0.01, double.MaxValue)] public decimal Amount { get; set; }
+    [Required] public long GlBankAccountId { get; set; }
+    [StringLength(100)] public string? Reference { get; set; }
+}
+
+public sealed class CreatePurchaseInvoiceRequest
+{
+    [Required] public int VendorId { get; set; }
+    [Required, StringLength(50)] public string VendorInvoiceNo { get; set; } = string.Empty;
+    [Required] public DateTime VendorInvoiceDate { get; set; }
+    [Required, MinLength(1)] public List<int> GrnIds { get; set; } = new();
+}
+
+public sealed class UpdatePurchaseInvoiceRequest
+{
+    [Required] public int VendorId { get; set; }
+    [Required, StringLength(50)] public string VendorInvoiceNo { get; set; } = string.Empty;
+    [Required] public DateTime VendorInvoiceDate { get; set; }
+    [Required, MinLength(1)] public List<int> GrnIds { get; set; } = new();
+}

Backend/ERPCore/Dtos/Production/RunDtos.cs

@@ -70,6 +70,35 @@ public sealed record RunEventDto(
     int EventId, int? RunStageId, RunStageEventType EventType, string? Note,
     JsonElement? Payload, int UserId, DateTime CreatedAt);
 
+/// <summary>
+/// One row of the produced-items report (<c>GET /production-runs/produced</c>) — the
+/// terminal output of a run that has produced something, costed the same way
+/// <c>PostReceiptAsync</c> costs the finished layer at approve (FR-MFG-13):
+/// <c>unitCost = (Σ ConsumedValue − Σ ReturnedValue) / (ProducedQty − ScrappedQty)</c>.
+/// One row per run — server validation (<see cref="ProductionGraphValidator"/> via
+/// FR-MFG-05) guarantees exactly one item-bearing output per run, always the terminal
+/// one, so run and produced line coincide 1:1.
+/// <para><c>UnitCost</c>/<c>TotalCost</c> are final only once <c>Status</c> is
+/// <c>Completed</c> — a leftover return can still shrink the pool between the terminal
+/// stage's Done and its Approve, same caveat as <see cref="CostPoolDto"/>.</para>
+/// </summary>
+public sealed record ProducedLineDto(
+    int RunId, string DocNo, ProductionRunStatus Status,
+    int TemplateId, string TemplateName,
+    int WarehouseId, string WarehouseName,
+    int ItemId, string ItemName,
+    decimal ProducedQty, decimal ScrappedQty, decimal GoodQty,
+    decimal UnitCost, decimal TotalCost,
+    DateTime CreatedAt, DateTime? CompletedAt);
+
+/// <summary>Aggregate footer for the produced-items report — totals over every row the filter
+/// matched, not just the current page (there is no pagination here, matching the Sales report
+/// convention of flat, filter-bounded rows).</summary>
+public sealed record ProducedSummaryDto(
+    int RunCount, decimal TotalProducedQty, decimal TotalScrappedQty, decimal TotalGoodQty, decimal TotalCost);
+
+public sealed record ProducedListResponseDto(IReadOnlyList<ProducedLineDto> Items, ProducedSummaryDto Summary);
+
 /// <summary>Full run graph (docs/30 §D.2 <c>GET /production-runs/{id}</c>).</summary>
 public sealed record RunGraphDto(
     int RunId, string DocNo, int TemplateId, string TemplateName,
@@ -99,8 +128,10 @@ public sealed class CreateRunRequest
 }
 
 /// <summary>
-/// Per-run scaling override (FR-MFG-08). Only accepted while the stage has not started
+/// Per-run scaling override (FR-MFG-08). Accepted before the stage starts, and — for a Stock
-/// (<c>409 STAGE_NOT_EDITABLE</c>).
+/// input only — while it is running too: raising <see cref="StageQuantityLine.PlannedQty"/>
+/// draws the extra amount from FIFO, lowering it returns the excess (<c>409
+/// STAGE_NOT_EDITABLE</c> for every other status).
 /// </summary>
 public sealed class UpdateStageQuantitiesRequest
 {
@@ -116,4 +147,11 @@ public sealed class StageQuantityLine
 
     [Range(0.0001, double.MaxValue)]
     public decimal PlannedQty { get; set; }
+
+    /// <summary>
+    /// Required only when this line lowers a running Stock input below what it has already
+    /// consumed — the excess is returned to stock the same way <c>ReturnLeftoverAsync</c>
+    /// does, and that always needs a reason (FR-MFG-14). Ignored otherwise.
+    /// </summary>
+    public int? ReasonCodeId { get; set; }
 }

Backend/ERPCore/Dtos/Rbac/MeDtos.cs

@@ -2,5 +2,13 @@ namespace ERPCore.Dtos.Rbac;
 
 /// <summary>Response for `GET /api/v1/auth/me` — the frontend's authoritative source
 /// for the current user's role and permitted sidebar nav codes (replaces trusting
-/// the stale, client-only `roleId` cached in localStorage).</summary>
+/// the stale, client-only `roleId` cached in localStorage). <see cref="BranchId"/>/
-public sealed record MeResponseDto(string? RoleCode, string? RoleName, IReadOnlyList<string> NavCodes);
+/// <see cref="BranchName"/> come from the caller's linked <c>Employee</c> record, when
+/// one exists — null for a login with no Employee link. <see cref="IsAdmin"/> gates
+/// branch pickers client-side only (no server-side branch enforcement exists yet,
+/// see docs/BRANCH_ISOLATION_PLAN.md). <see cref="BranchingEnabled"/> mirrors the
+/// singleton <c>BranchConfig</c> toggle — when false the frontend hides branch pickers
+/// entirely rather than merely restricting them by role.</summary>
+public sealed record MeResponseDto(
+    string? RoleCode, string? RoleName, IReadOnlyList<string> NavCodes,
+    bool IsAdmin, int? BranchId, string? BranchName, bool BranchingEnabled);

Backend/ERPCore/Dtos/Sales/BundleSaleDtos.cs

@@ -51,7 +51,6 @@ public sealed class CreateBundleSaleTemplateLineRequest
 
 public sealed class CreateBundleSaleTemplateRequest
 {
-    [Required] public string TemplateCode { get; set; } = string.Empty;
     [Required] public string TemplateName { get; set; } = string.Empty;
     public string? Description { get; set; }
     [Required, MinLength(1)] public List<CreateBundleSaleTemplateLineRequest> Lines { get; set; } = new();

Backend/ERPCore/Dtos/Sales/SalesDayEndDtos.cs

@@ -8,11 +8,21 @@ namespace ERPCore.Dtos.Sales;
 /// Merges sales-slip and bundle-sale lines for the same item into one row.</summary>
 public sealed record SalesDayEndItemLineDto(int ItemId, string Sku, string Name, decimal Qty, decimal Revenue);
 
+/// <summary>Read-only visibility into that cashier's Sales Invoices for the date — informational
+/// only, appended to <see cref="SalesDayEndDto"/> and <see cref="SalesDayEndPreviewDto"/>.
+/// Invoices post their own GL entry on Confirm (SalesPostingService.PostInvoiceAsync) and have no
+/// DayEndId, so they're never locked against a close: these fields are computed live from current
+/// data on every read, unlike the frozen Slip/Bundle totals alongside them.</summary>
+public sealed record SalesDayEndInvoiceSummaryDto(
+    int InvoiceCount, decimal InvoiceSubtotal, decimal InvoiceDiscountTotal, decimal InvoiceTaxTotal,
+    decimal InvoiceGrandTotal, IReadOnlyList<string> InvoiceNumbers);
+
 public sealed record SalesDayEndDto(
     int SalesDayEndId, string DocNo, int CashierUserId, DateOnly BusinessDate,
     int SlipCount, int BundleCount, decimal Subtotal, decimal DiscountTotal, decimal TaxTotal, decimal GrandTotal,
     decimal CostOfGoodsSold, string? GlJournalNo, DateTime? GlPostedAt, int ClosedBy, DateTime ClosedAt,
-    IReadOnlyList<string> SlipNumbers, IReadOnlyList<string> BundleNumbers, IReadOnlyList<SalesDayEndItemLineDto> ItemBreakdown);
+    IReadOnlyList<string> SlipNumbers, IReadOnlyList<string> BundleNumbers, IReadOnlyList<SalesDayEndItemLineDto> ItemBreakdown,
+    SalesDayEndInvoiceSummaryDto Invoices);
 
 public sealed record SalesDayEndSummaryDto(
     int SalesDayEndId, string DocNo, int CashierUserId, DateOnly BusinessDate,
@@ -25,7 +35,8 @@ public sealed record SalesDayEndPreviewDto(
     int SlipCount, int BundleCount, decimal Subtotal, decimal DiscountTotal, decimal TaxTotal, decimal GrandTotal,
     IReadOnlyList<string> SlipNumbers, IReadOnlyList<string> BundleNumbers,
     IReadOnlyList<DraftSlipBlockingCloseDto> DraftSlipsBlockingClose,
-    IReadOnlyList<DraftBundleBlockingCloseDto> DraftBundleSalesBlockingClose);
+    IReadOnlyList<DraftBundleBlockingCloseDto> DraftBundleSalesBlockingClose,
+    SalesDayEndInvoiceSummaryDto Invoices);
 
 public sealed record DraftSlipBlockingCloseDto(int SalesSlipId, string SlipNo, decimal GrandTotal);
 public sealed record DraftBundleBlockingCloseDto(int BundleSaleId, string BundleNo, decimal GrandTotal);

Backend/ERPCore/Dtos/Sales/SalesInvoiceDtos.cs

@@ -15,14 +15,14 @@ public sealed record SalesInvoiceTotalsDto(
 
 public sealed record SalesInvoiceDto(
     int SalesInvoiceId, string InvoiceNo, DateTime InvoiceDate, int CustomerId,
-    string CustomerSnapshotName, string? CustomerSnapshotTaxNo, int WarehouseId,
+    string CustomerSnapshotName, string? CustomerSnapshotTaxNo, int WarehouseId, int BranchId,
     SalesInvoiceType InvoiceType, SalesInvoiceStatus Status, int CreatedBy, DateTime CreatedAt,
     DateTime? UpdatedAt, string? GlJournalNo, DateTime? GlPostedAt,
     SalesInvoiceTotalsDto Totals, IReadOnlyList<SalesInvoiceLineDto> Lines);
 
 public sealed record SalesInvoiceSummaryDto(
     int SalesInvoiceId, string InvoiceNo, DateTime InvoiceDate, int CustomerId,
-    string CustomerSnapshotName, int WarehouseId, SalesInvoiceType InvoiceType,
+    string CustomerSnapshotName, int WarehouseId, int BranchId, SalesInvoiceType InvoiceType,
     SalesInvoiceStatus Status, SalesInvoiceTotalsDto Totals, DateTime CreatedAt, string? GlJournalNo);
 
 public sealed record SalesInvoicePaymentDto(
@@ -65,6 +65,9 @@ public sealed class CreateSalesInvoiceRequest
 {
     [Required] public int CustomerId { get; set; }
     [Required] public int WarehouseId { get; set; }
+    /// <summary>Owning branch — warehouses are shared, so this is what actually scopes the
+    /// document (resolved via IBranchConfigService).</summary>
+    [Required] public int BranchId { get; set; }
     [Required, EnumDataType(typeof(SalesInvoiceType))] public SalesInvoiceType InvoiceType { get; set; } = SalesInvoiceType.B2C;
     [Required, MinLength(1)] public List<CreateSalesInvoiceLineRequest> Lines { get; set; } = new();
 }
@@ -73,6 +76,9 @@ public sealed class UpdateSalesInvoiceRequest
 {
     [Required] public int CustomerId { get; set; }
     [Required] public int WarehouseId { get; set; }
+    /// <summary>Owning branch — warehouses are shared, so this is what actually scopes the
+    /// document (resolved via IBranchConfigService).</summary>
+    [Required] public int BranchId { get; set; }
     [Required, EnumDataType(typeof(SalesInvoiceType))] public SalesInvoiceType InvoiceType { get; set; } = SalesInvoiceType.B2C;
     [Required, MinLength(1)] public List<CreateSalesInvoiceLineRequest> Lines { get; set; } = new();
 }

Backend/ERPCore/Dtos/Sales/SalesPromotionSuggestionDtos.cs

@@ -4,7 +4,7 @@ public sealed record SalesFreeIssueRewardOptionDto(
     int ItemId,
     string Sku,
     string Name,
-    decimal? SalePrice);
+    decimal? SellingFlatPrice);
 
 public sealed record SalesFreeIssueSuggestionLineDto(
     int SalesSlipLineId,
@@ -20,4 +20,4 @@ public sealed record SalesFreeIssueSuggestionDto(
     int SalesSlipId,
     string SlipNo,
     DateTime SlipDate,
-    IReadOnlyList<SalesFreeIssueSuggestionLineDto> Lines);
+    IReadOnlyList<SalesFreeIssueSuggestionLineDto> Lines);

Backend/ERPCore/Dtos/Stock/AdjustmentDtos.cs

@@ -8,13 +8,13 @@ namespace ERPCore.Dtos.Stock;
 public sealed record AdjustmentLineDto(int AdjLineId, int ItemId, int? BinId, int? BatchId, decimal QtyDelta);
 
 public sealed record AdjustmentDto(
-    int AdjustmentId, string DocNo, int WarehouseId, int ReasonCodeId, AdjustmentStatus Status,
+    int AdjustmentId, string DocNo, int WarehouseId, int BranchId, int ReasonCodeId, AdjustmentStatus Status,
     int CreatedBy, DateTime CreatedAt, string? GlJournalNo, DateTime? GlPostedAt,
     IReadOnlyList<AdjustmentLineDto> Lines, IReadOnlyList<int> LedgerRefs);
 
 /// <summary>Row shape for <c>GET /stock-adjustments</c> — no lines/ledgerRefs (those need a per-row query).</summary>
 public sealed record AdjustmentSummaryDto(
-    int AdjustmentId, string DocNo, int WarehouseId, int ReasonCodeId, AdjustmentStatus Status,
+    int AdjustmentId, string DocNo, int WarehouseId, int BranchId, int ReasonCodeId, AdjustmentStatus Status,
     int CreatedBy, DateTime CreatedAt, int LineCount, string? GlJournalNo);
 
 // Requests ----------------------------------------------------------------------
@@ -31,6 +31,9 @@ public sealed class CreateAdjustmentLineInput
 public sealed class CreateAdjustmentRequest
 {
     [Required] public int WarehouseId { get; set; }
+    /// <summary>Owning branch — warehouses are shared, so this is what actually scopes the
+    /// document (resolved via IBranchConfigService).</summary>
+    [Required] public int BranchId { get; set; }
     /// <summary>Nullable so an omitted value is a distinct <c>REASON_CODE_REQUIRED</c> error, not 0.</summary>
     public int? ReasonCodeId { get; set; }
     [Required, MinLength(1)] public List<CreateAdjustmentLineInput> Lines { get; set; } = new();

Backend/ERPCore/Dtos/Stock/CountDtos.cs

@@ -8,12 +8,12 @@ namespace ERPCore.Dtos.Stock;
 public sealed record CountLineDto(int CountLineId, int ItemId, int? BinId, decimal SystemQty, decimal? CountedQty, decimal? Variance);
 
 public sealed record CountDto(
-    int CountId, string DocNo, int WarehouseId, CountType CountType, CountStatus Status,
+    int CountId, string DocNo, int WarehouseId, int BranchId, CountType CountType, CountStatus Status,
     int CreatedBy, DateTime CreatedAt, IReadOnlyList<CountLineDto> Lines);
 
 /// <summary>Row shape for <c>GET /stock-counts</c> — line count instead of the lines themselves.</summary>
 public sealed record CountSummaryDto(
-    int CountId, string DocNo, int WarehouseId, CountType CountType, CountStatus Status,
+    int CountId, string DocNo, int WarehouseId, int BranchId, CountType CountType, CountStatus Status,
     int CreatedBy, DateTime CreatedAt, int LineCount);
 
 public sealed record CountPostResultDto(int CountId, CountStatus Status, int? AdjustmentId, string? GlJournalNo, IReadOnlyList<int> LedgerRefs);
@@ -23,6 +23,9 @@ public sealed record CountPostResultDto(int CountId, CountStatus Status, int? Ad
 public sealed class CreateCountRequest
 {
     [Required] public int WarehouseId { get; set; }
+    /// <summary>Owning branch — warehouses are shared, so this is what actually scopes the
+    /// document (resolved via IBranchConfigService).</summary>
+    [Required] public int BranchId { get; set; }
     [Required, EnumDataType(typeof(CountType))] public CountType CountType { get; set; }
     [Required, MinLength(1)] public List<int> ItemIds { get; set; } = new();
 }

Backend/ERPCore/Dtos/Stock/TransferDtos.cs

@@ -9,12 +9,12 @@ public sealed record TransferLineDto(
     int TransferLineId, int ItemId, int? SrcBinId, int? DestBinId, int? BatchId, decimal Qty, decimal QtyReceived);
 
 public sealed record TransferDto(
-    int TransferId, string DocNo, int SrcWarehouseId, int DestWarehouseId,
+    int TransferId, string DocNo, int SrcWarehouseId, int DestWarehouseId, int BranchId,
     TransferStatus Status, int CreatedBy, DateTime CreatedAt, IReadOnlyList<TransferLineDto> Lines);
 
 /// <summary>Row shape for <c>GET /stock-transfers</c> — line count instead of the lines themselves.</summary>
 public sealed record TransferSummaryDto(
-    int TransferId, string DocNo, int SrcWarehouseId, int DestWarehouseId,
+    int TransferId, string DocNo, int SrcWarehouseId, int DestWarehouseId, int BranchId,
     TransferStatus Status, int CreatedBy, DateTime CreatedAt, int LineCount);
 
 public sealed record ConsumedLayerDto(int LayerId, decimal QtyConsumed, decimal UnitCost);
@@ -42,6 +42,9 @@ public sealed class CreateTransferRequest
 {
     [Required] public int SrcWarehouseId { get; set; }
     [Required] public int DestWarehouseId { get; set; }
+    /// <summary>Owning branch for this transfer — warehouses are shared, so this is what
+    /// actually scopes the document (resolved via IBranchConfigService).</summary>
+    [Required] public int BranchId { get; set; }
     [Required, MinLength(1)] public List<CreateTransferLineInput> Lines { get; set; } = new();
 }
 

Backend/ERPCore/Dtos/Users/UserDtos.cs

@@ -30,6 +30,22 @@ public sealed class CreateUserRequest
     /// email-lookup — never automatic, even on an exact email match (docs/12-BACKEND-HRM.md A.5).
     /// </summary>
     public int? LinkEmployeeId { get; set; }
+
+    /// <summary>
+    /// Required, together with <see cref="DepartmentId"/>/<see cref="DesignationId"/>/
+    /// <see cref="EmploymentTypeId"/>/<see cref="WorkShiftId"/>/<see cref="BranchId"/>, whenever
+    /// the assigned Role is not Admin and <see cref="LinkEmployeeId"/> is not supplied: creates
+    /// the linked Employee record whose BranchId is what actually scopes this account to one
+    /// branch (see BranchAccessService.EnsureBranchVisibleAsync).
+    /// </summary>
+    public string? EmployeeCode { get; set; }
+    public int? BranchId { get; set; }
+    public int? DepartmentId { get; set; }
+    public int? DesignationId { get; set; }
+    public int? EmploymentTypeId { get; set; }
+    public int? WorkShiftId { get; set; }
+    /// <summary>Defaults to today when omitted.</summary>
+    public DateTime? HireDate { get; set; }
 }
 
 public sealed class UpdateUserRoleRequest

Backend/ERPCore/Dtos/Warehouses/WarehouseDtos.cs

@@ -2,8 +2,10 @@ using System.ComponentModel.DataAnnotations;
 
 namespace ERPCore.Dtos.Warehouses;
 
-/// <summary>Warehouse resource (docs/11-BACKEND-PHASE1.md §2.5).</summary>
+/// <summary>Warehouse resource (docs/11-BACKEND-PHASE1.md §2.5). <see cref="BranchId"/> is
-public sealed record WarehouseDto(int WarehouseId, string Code, string Name);
+/// the anchor `docs/BRANCH_ISOLATION_PLAN.md` uses to branch-scope everything that carries
+/// a `warehouseId` (Sales, GRN, stock, ...) without a column on every one of those entities.</summary>
+public sealed record WarehouseDto(int WarehouseId, string Code, string Name, int BranchId, string? BranchName);
 
 /// <summary>Bin/location resource (docs/11 §2.5).</summary>
 public sealed record BinDto(int BinId, int WarehouseId, string Code, string? BinType);
@@ -12,6 +14,7 @@ public sealed class CreateWarehouseRequest
 {
     [Required, StringLength(50)] public string Code { get; set; } = string.Empty;
     [Required, StringLength(200)] public string Name { get; set; } = string.Empty;
+    [Required] public int BranchId { get; set; }
 }
 
 public sealed class CreateBinRequest

Backend/ERPCore/Infra/Auth/CurrentUser.cs

@@ -31,4 +31,8 @@ public sealed class CurrentUser : ICurrentUser
     }
 
     public int AuditUserId => int.TryParse(UserId, out var id) ? id : User.SystemUserId;
+
+    public string? RoleCode => _accessor.HttpContext?.User?.FindFirstValue(AuthHexClaims.RoleCode);
+
+    public bool IsAdmin => string.Equals(RoleCode?.Trim(), "Admin", StringComparison.OrdinalIgnoreCase);
 }

Backend/ERPCore/Infra/Auth/ICurrentUser.cs

@@ -19,4 +19,14 @@ public interface ICurrentUser
 
     /// <summary>True when the request carries an authenticated principal.</summary>
     bool IsAuthenticated { get; }
+
+    /// <summary>The AuthHex <c>RoleCode</c> claim verbatim, or null if absent/unauthenticated.</summary>
+    string? RoleCode { get; }
+
+    /// <summary>
+    /// True when <see cref="RoleCode"/> is "Admin" (case-insensitive — AuthHex mints the claim
+    /// independently of ERPCore's stored casing). Mirrors <c>RoleService.GetMeAsync</c>'s check;
+    /// the only role that bypasses branch-scoping (see <see cref="Services.Interfaces.IBranchAccessService"/>).
+    /// </summary>
+    bool IsAdmin { get; }
 }

Backend/ERPCore/Infra/Persistence/Configurations/BranchConfigConfiguration.cs

@@ -0,0 +1,33 @@
+using ERPCore.Domain.Entities;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace ERPCore.Infra.Persistence.Configurations;
+
+/// <summary>
+/// Configures the singleton branch-configuration row. The check constraint is what makes
+/// "singleton" a database guarantee rather than a convention (mirrors ProductConfig).
+/// </summary>
+public sealed class BranchConfigConfiguration : IEntityTypeConfiguration<BranchConfig>
+{
+    public void Configure(EntityTypeBuilder<BranchConfig> builder)
+    {
+        builder.ToTable("branch_config", t =>
+            t.HasCheckConstraint("ck_branch_config_singleton", $"\"ConfigId\" = {BranchConfig.SingletonId}"));
+
+        builder.HasKey(c => c.ConfigId);
+
+        // The id is fixed, never generated — there is exactly one row, seeded by DataSeeder.
+        builder.Property(c => c.ConfigId).ValueGeneratedNever();
+
+        builder.Property(c => c.BranchingEnabled).IsRequired().HasDefaultValue(true);
+
+        // PostgreSQL xmin system column as the optimistic concurrency token (ETag).
+        builder.Property(c => c.RowVersion).IsRowVersion();
+
+        builder.HasOne(c => c.UpdatedByUser)
+            .WithMany()
+            .HasForeignKey(c => c.UpdatedBy)
+            .OnDelete(DeleteBehavior.Restrict);
+    }
+}

Backend/ERPCore/Infra/Persistence/Configurations/BranchConfiguration.cs

@@ -16,6 +16,7 @@ public sealed class BranchConfiguration : IEntityTypeConfiguration<Branch>
         builder.HasIndex(b => b.Code).IsUnique();
         builder.Property(b => b.Name).IsRequired().HasMaxLength(200);
         builder.Property(b => b.Address).HasMaxLength(500);
+        builder.Property(b => b.PhoneNumber).HasMaxLength(30);
 
         builder.Property(b => b.Status)
             .HasConversion<string>().HasMaxLength(20).IsRequired()

Backend/ERPCore/Infra/Persistence/Configurations/GrnConfiguration.cs

@@ -17,38 +17,18 @@ public sealed class GrnConfiguration : IEntityTypeConfiguration<Grn>
         builder.Property(g => g.Status).HasConversion<string>().HasMaxLength(20).IsRequired();
         builder.Property(g => g.CreatedAt).IsRequired();
         builder.Property(g => g.GlJournalNo).HasMaxLength(30);
-        builder.Property(g => g.PaidAmount).HasPrecision(18, 4);
-        builder.Property(g => g.BalanceAmount).HasPrecision(18, 4);
         builder.Property(g => g.RowVersion).IsRowVersion();
 
         builder.HasOne(g => g.PurchaseOrder).WithMany().HasForeignKey(g => g.PoId).OnDelete(DeleteBehavior.Restrict);
         builder.HasOne(g => g.Vendor).WithMany().HasForeignKey(g => g.VendorId).OnDelete(DeleteBehavior.Restrict);
         builder.HasOne(g => g.Warehouse).WithMany().HasForeignKey(g => g.WarehouseId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(g => g.Branch).WithMany().HasForeignKey(g => g.BranchId).OnDelete(DeleteBehavior.Restrict);
         builder.HasOne(g => g.Creator).WithMany().HasForeignKey(g => g.CreatedBy).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(g => g.PurchaseInvoice).WithMany().HasForeignKey(g => g.PurchaseInvoiceId).OnDelete(DeleteBehavior.Restrict);
 
         builder.HasIndex(g => g.Status);
         builder.HasIndex(g => g.PoId);
-    }
+        builder.HasIndex(g => g.BranchId);
-}
-
-public sealed class GrnPaymentConfiguration : IEntityTypeConfiguration<GrnPayment>
-{
-    public void Configure(EntityTypeBuilder<GrnPayment> builder)
-    {
-        builder.ToTable("grn_payments");
-        builder.HasKey(p => p.GrnPaymentId);
-
-        builder.Property(p => p.Amount).HasPrecision(18, 4);
-        builder.Property(p => p.PaymentDate).IsRequired();
-        builder.Property(p => p.BankAccountName).IsRequired().HasMaxLength(200);
-        builder.Property(p => p.Reference).HasMaxLength(100);
-        builder.Property(p => p.GlJournalNo).HasMaxLength(30);
-        builder.Property(p => p.CreatedAt).IsRequired();
-
-        builder.HasOne(p => p.Grn).WithMany(g => g.Payments).HasForeignKey(p => p.GrnId).OnDelete(DeleteBehavior.Restrict);
-        builder.HasOne(p => p.Creator).WithMany().HasForeignKey(p => p.CreatedBy).OnDelete(DeleteBehavior.Restrict);
-
-        builder.HasIndex(p => p.GrnId);
     }
 }
 

Backend/ERPCore/Infra/Persistence/Configurations/ItemConfiguration.cs

@@ -20,7 +20,9 @@ public sealed class ItemConfiguration : IEntityTypeConfiguration<Item>
         builder.Property(i => i.TaxClass).HasMaxLength(20);
 
         // Sales-only fixed selling price; nullable (null ⇒ sell at stock/FIFO value).
-        builder.Property(i => i.SalePrice).HasPrecision(18, 4);
+        builder.Property(i => i.SellingMinPrice).HasPrecision(18, 4);
+        builder.Property(i => i.SellingMaxPrice).HasPrecision(18, 4);
+        builder.Property(i => i.SellingFlatPrice).HasPrecision(18, 4);
 
         // Optional content size (how much one stocked pack holds). All four are nullable
         // together: null ⇒ the item has no measurable content. The base pair is derived

Backend/ERPCore/Infra/Persistence/Configurations/NavItemConfiguration.cs

@@ -39,7 +39,8 @@ public sealed class NavItemConfiguration : IEntityTypeConfiguration<NavItem>
             new NavItem { NavItemId = 10, Code = "help", Label = "Help", Href = "/dashboard/help", SortOrder = 10 },
             new NavItem { NavItemId = 11, Code = "ledgers", Label = "Ledgers", Href = "/dashboard/ledgers", SortOrder = 11 },
             new NavItem { NavItemId = 12, Code = "accounts", Label = "Accounts", Href = "/dashboard/accounts", SortOrder = 12 },
-            new NavItem { NavItemId = 13, Code = "sales", Label = "Sales", Href = "/dashboard/sales", SortOrder = 13 }
+            new NavItem { NavItemId = 13, Code = "sales", Label = "Sales", Href = "/dashboard/sales", SortOrder = 13 },
+            new NavItem { NavItemId = 14, Code = "production", Label = "Production", Href = "/dashboard/production", SortOrder = 14 }
         );
     }
 }

Backend/ERPCore/Infra/Persistence/Configurations/NotificationConfigConfiguration.cs

@@ -0,0 +1,29 @@
+using ERPCore.Domain.Entities;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace ERPCore.Infra.Persistence.Configurations;
+
+public sealed class NotificationConfigConfiguration : IEntityTypeConfiguration<NotificationConfig>
+{
+    public void Configure(EntityTypeBuilder<NotificationConfig> builder)
+    {
+        builder.ToTable("notification_config", t =>
+            t.HasCheckConstraint("ck_notification_config_singleton", $"\"NotificationConfigId\" = {NotificationConfig.SingletonId}"));
+
+        builder.HasKey(c => c.NotificationConfigId);
+        builder.Property(c => c.NotificationConfigId).ValueGeneratedNever();
+
+        builder.Property(c => c.RowVersion).IsRowVersion();
+
+        builder.HasMany(c => c.Modules)
+            .WithOne(m => m.NotificationConfig)
+            .HasForeignKey(m => m.NotificationConfigId)
+            .OnDelete(DeleteBehavior.Cascade);
+
+        builder.HasOne(c => c.UpdatedByUser)
+            .WithMany()
+            .HasForeignKey(c => c.UpdatedBy)
+            .OnDelete(DeleteBehavior.Restrict);
+    }
+}

Backend/ERPCore/Infra/Persistence/Configurations/NotificationConfigModuleConfiguration.cs

@@ -0,0 +1,21 @@
+using ERPCore.Domain.Entities;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace ERPCore.Infra.Persistence.Configurations;
+
+public sealed class NotificationConfigModuleConfiguration : IEntityTypeConfiguration<NotificationConfigModule>
+{
+    public void Configure(EntityTypeBuilder<NotificationConfigModule> builder)
+    {
+        builder.ToTable("notification_config_modules");
+        builder.HasKey(m => m.NotificationConfigModuleId);
+
+        builder.Property(m => m.ModuleKey).IsRequired().HasMaxLength(100);
+        builder.HasIndex(m => m.ModuleKey).IsUnique();
+
+        builder.Property(m => m.EmailEnabled).IsRequired().HasDefaultValue(false);
+        builder.Property(m => m.SmsEnabled).IsRequired().HasDefaultValue(false);
+        builder.Property(m => m.InAppEnabled).IsRequired().HasDefaultValue(false);
+    }
+}

Backend/ERPCore/Infra/Persistence/Configurations/PermissionConfiguration.cs

@@ -61,7 +61,13 @@ public sealed class PermissionConfiguration : IEntityTypeConfiguration<Permissio
             new Permission { PermissionId = 26, Code = "NAV:accounts.bank-accounts", SubNavItemId = 15 },
             new Permission { PermissionId = 32, Code = "NAV:accounts", NavItemId = 12 },
             new Permission { PermissionId = 33, Code = "NAV:accounts.cheque-books", SubNavItemId = 21 },
-            new Permission { PermissionId = 34, Code = "NAV:accounts.received-cheques", SubNavItemId = 22 }
+            new Permission { PermissionId = 34, Code = "NAV:accounts.received-cheques", SubNavItemId = 22 },
+            new Permission { PermissionId = 35, Code = "NAV:production", NavItemId = 14 },
+            new Permission { PermissionId = 36, Code = "NAV:production.templates", SubNavItemId = 27 },
+            new Permission { PermissionId = 37, Code = "NAV:production.runs", SubNavItemId = 25 },
+            new Permission { PermissionId = 38, Code = "NAV:production.produced", SubNavItemId = 26 },
+            new Permission { PermissionId = 39, Code = "NAV:procurement.purchase-invoices", SubNavItemId = 28 },
+            new Permission { PermissionId = 40, Code = "NAV:settings.branches", SubNavItemId = 29 }
         );
     }
 }

Backend/ERPCore/Infra/Persistence/Configurations/ProductConfigConfiguration.cs

@@ -25,6 +25,10 @@ public sealed class ProductConfigConfiguration : IEntityTypeConfiguration<Produc
         builder.Property(c => c.SubcategoriesEnabled).IsRequired().HasDefaultValue(true);
         builder.Property(c => c.BrandsEnabled).IsRequired().HasDefaultValue(true);
         builder.Property(c => c.ItemTypesEnabled).IsRequired().HasDefaultValue(true);
+        builder.Property(c => c.SellingPricesEnabled).IsRequired().HasDefaultValue(true);
+        builder.Property(c => c.SerialNumbersEnabled).IsRequired().HasDefaultValue(true);
+        builder.Property(c => c.BatchListsEnabled).IsRequired().HasDefaultValue(true);
+        builder.Property(c => c.WarrantyPeriodsEnabled).IsRequired().HasDefaultValue(true);
 
         // PostgreSQL xmin system column as the optimistic concurrency token (ETag).
         builder.Property(c => c.RowVersion).IsRowVersion();

Backend/ERPCore/Infra/Persistence/Configurations/PurchaseInvoiceConfiguration.cs

@@ -0,0 +1,97 @@
+using ERPCore.Domain.Entities;
+using ERPCore.Domain.Enums;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace ERPCore.Infra.Persistence.Configurations;
+
+public sealed class PurchaseInvoiceConfiguration : IEntityTypeConfiguration<PurchaseInvoice>
+{
+    public void Configure(EntityTypeBuilder<PurchaseInvoice> builder)
+    {
+        builder.ToTable("purchase_invoices");
+        builder.HasKey(x => x.PurchaseInvoiceId);
+
+        builder.Property(x => x.DocNo).IsRequired().HasMaxLength(30);
+        builder.HasIndex(x => x.DocNo).IsUnique();
+
+        builder.Property(x => x.VendorInvoiceNo).IsRequired().HasMaxLength(50);
+        builder.Property(x => x.VendorInvoiceDate).IsRequired();
+        // A vendor invoice number is only meaningful per-vendor; the service also excludes
+        // Cancelled invoices from the duplicate check, so this composite index is a coarse
+        // backstop (it does not distinguish Cancelled rows) rather than the sole enforcement.
+        builder.HasIndex(x => new { x.VendorId, x.VendorInvoiceNo });
+
+        builder.HasOne(x => x.Vendor)
+            .WithMany()
+            .HasForeignKey(x => x.VendorId)
+            .OnDelete(DeleteBehavior.Restrict);
+
+        builder.Property(x => x.VendorSnapshotName).IsRequired().HasMaxLength(200);
+        builder.Property(x => x.VendorSnapshotTaxNo).HasMaxLength(50);
+
+        builder.Property(x => x.Status)
+            .HasConversion<string>().HasMaxLength(20).IsRequired()
+            .HasDefaultValue(PurchaseInvoiceStatus.Draft);
+
+        foreach (var p in new[] { nameof(PurchaseInvoice.Subtotal), nameof(PurchaseInvoice.VatTotal), nameof(PurchaseInvoice.GrandTotal), nameof(PurchaseInvoice.PaidAmount), nameof(PurchaseInvoice.BalanceAmount) })
+            builder.Property<decimal>(p).HasPrecision(18, 4);
+        builder.Property(x => x.GlJournalNo).HasMaxLength(30);
+
+        builder.HasOne(x => x.Creator).WithMany().HasForeignKey(x => x.CreatedBy).OnDelete(DeleteBehavior.Restrict);
+        builder.Property(x => x.CreatedAt).IsRequired();
+        builder.Property(x => x.RowVersion).IsRowVersion();
+
+        builder.HasIndex(x => x.Status);
+        builder.HasIndex(x => x.VendorId);
+
+        builder.HasMany(x => x.Lines)
+            .WithOne(x => x.PurchaseInvoice)
+            .HasForeignKey(x => x.PurchaseInvoiceId)
+            .OnDelete(DeleteBehavior.Cascade);
+    }
+}
+
+public sealed class PurchaseInvoiceLineConfiguration : IEntityTypeConfiguration<PurchaseInvoiceLine>
+{
+    public void Configure(EntityTypeBuilder<PurchaseInvoiceLine> builder)
+    {
+        builder.ToTable("purchase_invoice_lines");
+        builder.HasKey(x => x.PurchaseInvoiceLineId);
+
+        builder.Property(x => x.Subtotal).HasPrecision(18, 4);
+        builder.Property(x => x.VatTotal).HasPrecision(18, 4);
+        builder.Property(x => x.LineTotal).HasPrecision(18, 4);
+
+        builder.HasOne(x => x.Grn)
+            .WithMany()
+            .HasForeignKey(x => x.GrnId)
+            .OnDelete(DeleteBehavior.Restrict);
+
+        // A GRN can be consolidated onto at most one active line at a time — cancelling the
+        // invoice removes its lines and frees the GRN (PurchaseInvoiceService.CancelAsync), so
+        // this stays enforceable rather than blocking a later re-invoice of the same GRN.
+        builder.HasIndex(x => x.GrnId).IsUnique();
+    }
+}
+
+public sealed class PurchaseInvoicePaymentConfiguration : IEntityTypeConfiguration<PurchaseInvoicePayment>
+{
+    public void Configure(EntityTypeBuilder<PurchaseInvoicePayment> builder)
+    {
+        builder.ToTable("purchase_invoice_payments");
+        builder.HasKey(p => p.PurchaseInvoicePaymentId);
+
+        builder.Property(p => p.Amount).HasPrecision(18, 4);
+        builder.Property(p => p.PaymentDate).IsRequired();
+        builder.Property(p => p.BankAccountName).IsRequired().HasMaxLength(200);
+        builder.Property(p => p.Reference).HasMaxLength(100);
+        builder.Property(p => p.GlJournalNo).HasMaxLength(30);
+        builder.Property(p => p.CreatedAt).IsRequired();
+
+        builder.HasOne(p => p.PurchaseInvoice).WithMany(x => x.Payments).HasForeignKey(p => p.PurchaseInvoiceId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(p => p.Creator).WithMany().HasForeignKey(p => p.CreatedBy).OnDelete(DeleteBehavior.Restrict);
+
+        builder.HasIndex(p => p.PurchaseInvoiceId);
+    }
+}

Backend/ERPCore/Infra/Persistence/Configurations/SalesInvoiceConfiguration.cs

@@ -30,6 +30,11 @@ public sealed class SalesInvoiceConfiguration : IEntityTypeConfiguration<SalesIn
             .HasForeignKey(x => x.WarehouseId)
             .OnDelete(DeleteBehavior.Restrict);
 
+        builder.HasOne(x => x.Branch)
+            .WithMany()
+            .HasForeignKey(x => x.BranchId)
+            .OnDelete(DeleteBehavior.Restrict);
+
         builder.Property(x => x.InvoiceType)
             .HasConversion<string>().HasMaxLength(20).IsRequired()
             .HasDefaultValue(SalesInvoiceType.B2C);
@@ -47,6 +52,7 @@ public sealed class SalesInvoiceConfiguration : IEntityTypeConfiguration<SalesIn
 
         builder.HasIndex(x => x.Status);
         builder.HasIndex(x => x.InvoiceDate);
+        builder.HasIndex(x => x.BranchId);
 
         builder.HasMany(x => x.Lines)
             .WithOne(x => x.SalesInvoice)

Backend/ERPCore/Infra/Persistence/Configurations/StockAdjustmentConfiguration.cs

@@ -21,7 +21,10 @@ public sealed class StockAdjustmentConfiguration : IEntityTypeConfiguration<Stoc
 
         builder.HasOne(a => a.Warehouse).WithMany().HasForeignKey(a => a.WarehouseId).OnDelete(DeleteBehavior.Restrict);
         builder.HasOne(a => a.ReasonCode).WithMany().HasForeignKey(a => a.ReasonCodeId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(a => a.Branch).WithMany().HasForeignKey(a => a.BranchId).OnDelete(DeleteBehavior.Restrict);
         builder.HasOne(a => a.Creator).WithMany().HasForeignKey(a => a.CreatedBy).OnDelete(DeleteBehavior.Restrict);
+
+        builder.HasIndex(a => a.BranchId);
     }
 }
 

Backend/ERPCore/Infra/Persistence/Configurations/StockCountConfiguration.cs

@@ -20,9 +20,11 @@ public sealed class StockCountConfiguration : IEntityTypeConfiguration<StockCoun
         builder.Property(c => c.RowVersion).IsRowVersion();
 
         builder.HasOne(c => c.Warehouse).WithMany().HasForeignKey(c => c.WarehouseId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(c => c.Branch).WithMany().HasForeignKey(c => c.BranchId).OnDelete(DeleteBehavior.Restrict);
         builder.HasOne(c => c.Creator).WithMany().HasForeignKey(c => c.CreatedBy).OnDelete(DeleteBehavior.Restrict);
 
         builder.HasIndex(c => c.Status);
+        builder.HasIndex(c => c.BranchId);
     }
 }
 

Backend/ERPCore/Infra/Persistence/Configurations/StockTransferConfiguration.cs

@@ -20,9 +20,11 @@ public sealed class StockTransferConfiguration : IEntityTypeConfiguration<StockT
 
         builder.HasOne(t => t.SrcWarehouse).WithMany().HasForeignKey(t => t.SrcWarehouseId).OnDelete(DeleteBehavior.Restrict);
         builder.HasOne(t => t.DestWarehouse).WithMany().HasForeignKey(t => t.DestWarehouseId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasOne(t => t.Branch).WithMany().HasForeignKey(t => t.BranchId).OnDelete(DeleteBehavior.Restrict);
         builder.HasOne(t => t.Creator).WithMany().HasForeignKey(t => t.CreatedBy).OnDelete(DeleteBehavior.Restrict);
 
         builder.HasIndex(t => t.Status);
+        builder.HasIndex(t => t.BranchId);
     }
 }
 

Backend/ERPCore/Infra/Persistence/Configurations/SubNavItemConfiguration.cs

@@ -31,8 +31,10 @@ public sealed class SubNavItemConfiguration : IEntityTypeConfiguration<SubNavIte
             new SubNavItem { SubNavItemId = 4, NavItemId = 2, Code = "products.item-type", Label = "Item Type", Href = "/dashboard/products/item-types", SortOrder = 4 },
             new SubNavItem { SubNavItemId = 5, NavItemId = 2, Code = "products.uom", Label = "UOM", Href = "/dashboard/products/uoms", SortOrder = 5 },
             new SubNavItem { SubNavItemId = 6, NavItemId = 2, Code = "products.configuration", Label = "Configuration", Href = "/dashboard/products/settings", SortOrder = 6 },
+            new SubNavItem { SubNavItemId = 29, NavItemId = 9, Code = "settings.branches", Label = "Branches", Href = "/dashboard/settings/branches", SortOrder = 0 },
             new SubNavItem { SubNavItemId = 7, NavItemId = 9, Code = "settings.roles", Label = "Roles", Href = "/dashboard/settings/roles", SortOrder = 1 },
             new SubNavItem { SubNavItemId = 8, NavItemId = 9, Code = "settings.users", Label = "Users", Href = "/dashboard/settings/users", SortOrder = 2 },
+            new SubNavItem { SubNavItemId = 24, NavItemId = 9, Code = "settings.notification-config", Label = "Notification Config", Href = "/dashboard/settings/notification-config", SortOrder = 3 },
             new SubNavItem { SubNavItemId = 23, NavItemId = 13, Code = "sales.bundle-sales", Label = "Bundle Sales", Href = "/dashboard/sales/bundles", SortOrder = 1 },
             // Procurement (NavItemId 4) children — mirror the hub page order.
             // IDs 17-20 (not 9-12): 9-12 were already claimed by the Ledgers sub-items below;
@@ -41,6 +43,7 @@ public sealed class SubNavItemConfiguration : IEntityTypeConfiguration<SubNavIte
             new SubNavItem { SubNavItemId = 18, NavItemId = 4, Code = "procurement.rfqs", Label = "RFQs", Href = "/dashboard/procurement/rfqs", SortOrder = 2 },
             new SubNavItem { SubNavItemId = 19, NavItemId = 4, Code = "procurement.purchase-orders", Label = "Purchase Orders", Href = "/dashboard/procurement/purchase-orders", SortOrder = 3 },
             new SubNavItem { SubNavItemId = 20, NavItemId = 4, Code = "procurement.purchase-returns", Label = "Purchase Returns", Href = "/dashboard/procurement/purchase-returns", SortOrder = 4 },
+            new SubNavItem { SubNavItemId = 28, NavItemId = 4, Code = "procurement.purchase-invoices", Label = "Purchase Invoices", Href = "/dashboard/procurement/purchase-invoices", SortOrder = 5 },
             new SubNavItem { SubNavItemId = 9, NavItemId = 11, Code = "ledgers.trial-balance", Label = "Trial Balance", Href = "/dashboard/ledgers/trial-balance", SortOrder = 1 },
             new SubNavItem { SubNavItemId = 10, NavItemId = 11, Code = "ledgers.balance-sheet", Label = "Balance Sheet", Href = "/dashboard/ledgers/balance-sheet", SortOrder = 2 },
             new SubNavItem { SubNavItemId = 11, NavItemId = 11, Code = "ledgers.general-ledger", Label = "General Ledger", Href = "/dashboard/ledgers/general-ledger", SortOrder = 3 },
@@ -53,7 +56,15 @@ public sealed class SubNavItemConfiguration : IEntityTypeConfiguration<SubNavIte
             // doesn't silently lose it just because the section it lives under changed.
             new SubNavItem { SubNavItemId = 15, NavItemId = 12, Code = "accounts.bank-accounts", Label = "Cash / Bank Accounts", Href = "/dashboard/accounts/bank-accounts", SortOrder = 1 },
             new SubNavItem { SubNavItemId = 21, NavItemId = 12, Code = "accounts.cheque-books", Label = "Cheque Books", Href = "/dashboard/accounts/cheque-books", SortOrder = 2 },
-            new SubNavItem { SubNavItemId = 22, NavItemId = 12, Code = "accounts.received-cheques", Label = "Received Cheques", Href = "/dashboard/accounts/received-cheques", SortOrder = 3 }
+            new SubNavItem { SubNavItemId = 22, NavItemId = 12, Code = "accounts.received-cheques", Label = "Received Cheques", Href = "/dashboard/accounts/received-cheques", SortOrder = 3 },
+            // Production (NavItemId 14) children — mirror the sidebar order (AppSidebar.tsx).
+            // ID 27 (not 24): 24 collides with settings.notification-config above — that ID was
+            // reused by mistake in migration 20260820100345, which upserts row 24 to become the
+            // notification-config item and silently overwrites this one. See migration
+            // FixProductionTemplatesSubNavItemIdConflict for the data repair.
+            new SubNavItem { SubNavItemId = 27, NavItemId = 14, Code = "production.templates", Label = "Templates", Href = "/dashboard/production/templates", SortOrder = 1 },
+            new SubNavItem { SubNavItemId = 25, NavItemId = 14, Code = "production.runs", Label = "Runs", Href = "/dashboard/production/runs", SortOrder = 2 },
+            new SubNavItem { SubNavItemId = 26, NavItemId = 14, Code = "production.produced", Label = "Produced", Href = "/dashboard/production/produced", SortOrder = 3 }
         );
     }
 }

Backend/ERPCore/Infra/Persistence/Configurations/WarehouseConfiguration.cs

@@ -15,5 +15,9 @@ public sealed class WarehouseConfiguration : IEntityTypeConfiguration<Warehouse>
         builder.HasIndex(w => w.Code).IsUnique();
 
         builder.Property(w => w.Name).IsRequired().HasMaxLength(200);
+
+        builder.HasOne(w => w.Branch).WithMany()
+            .HasForeignKey(w => w.BranchId).OnDelete(DeleteBehavior.Restrict);
+        builder.HasIndex(w => w.BranchId);
     }
 }

Backend/ERPCore/Infra/Persistence/DataSeeder.cs

@@ -43,8 +43,10 @@ public static class DataSeeder
     {
         var dirty = await SeedReasonCodesAsync(db, ct);
         dirty |= await SeedItemTypesAsync(db, ct);
-       // dirty |= await SeedCompanyProfileAsync(db, ct);
+        // dirty |= await SeedCompanyProfileAsync(db, ct);
         dirty |= await SeedProductConfigAsync(db, ct);
+        dirty |= await SeedBranchConfigAsync(db, ct);
+        dirty |= await SeedNotificationConfigAsync(db, ct);
         dirty |= await SeedSalesMastersAsync(db, ct);
         dirty |= await SeedSalesStockAsync(db, ct);
         dirty |= await SeedSalesAsync(db, ct);
@@ -100,7 +102,39 @@ public static class DataSeeder
             ConfigId = ProductConfig.SingletonId,
             SubcategoriesEnabled = true,
             BrandsEnabled = true,
-            ItemTypesEnabled = true
+            ItemTypesEnabled = true,
+            SellingPricesEnabled = true,
+            SerialNumbersEnabled = true,
+            BatchListsEnabled = true,
+            WarrantyPeriodsEnabled = true
+        });
+        return true;
+    }
+
+    /// <summary>
+    /// Ensures the singleton branch-config row exists. New deployments start with branching
+    /// on — today's mandatory-branch behaviour — so nothing changes for anyone until an
+    /// admin deliberately switches it off from Settings.
+    /// </summary>
+    private static async Task<bool> SeedBranchConfigAsync(ErpDbContext db, CancellationToken ct)
+    {
+        if (await db.BranchConfig.AnyAsync(c => c.ConfigId == BranchConfig.SingletonId, ct)) return false;
+
+        db.BranchConfig.Add(new BranchConfig
+        {
+            ConfigId = BranchConfig.SingletonId,
+            BranchingEnabled = true
+        });
+        return true;
+    }
+
+    private static async Task<bool> SeedNotificationConfigAsync(ErpDbContext db, CancellationToken ct)
+    {
+        if (await db.NotificationConfig.AnyAsync(c => c.NotificationConfigId == NotificationConfig.SingletonId, ct)) return false;
+
+        db.NotificationConfig.Add(new NotificationConfig
+        {
+            NotificationConfigId = NotificationConfig.SingletonId
         });
         return true;
     }
@@ -182,7 +216,7 @@ public static class DataSeeder
             WarehouseId = warehouse.WarehouseId,
             QtyReceived = 100m,
             QtyRemaining = 100m,
-            UnitCost = item.SalePrice.GetValueOrDefault() > 0m ? item.SalePrice.GetValueOrDefault() / 2m : 25m,
+            UnitCost = item.SellingFlatPrice.GetValueOrDefault() > 0m ? item.SellingFlatPrice.GetValueOrDefault() / 2m : 25m,
             ReceiptDate = DateTime.UtcNow.AddDays(-7)
         });
         db.StockLayers.Add(new StockLayer
@@ -191,7 +225,7 @@ public static class DataSeeder
             WarehouseId = warehouse.WarehouseId,
             QtyReceived = 5m,
             QtyRemaining = 5m,
-            UnitCost = secondItem.SalePrice.GetValueOrDefault() > 0m ? secondItem.SalePrice.GetValueOrDefault() / 2m : 15m,
+            UnitCost = secondItem.SellingFlatPrice.GetValueOrDefault() > 0m ? secondItem.SellingFlatPrice.GetValueOrDefault() / 2m : 15m,
             ReceiptDate = DateTime.UtcNow.AddDays(-6)
         });
         return true;
@@ -278,7 +312,7 @@ public static class DataSeeder
                 BaseUomId = uom.UomId,
                 StockNature = StockNature.Stocked,
                 TrackingMode = TrackingMode.None,
-                SalePrice = 100m,
+                SellingFlatPrice = 100m,
                 Status = EntityStatus.Active,
                 CreatedAt = now
             },
@@ -292,7 +326,7 @@ public static class DataSeeder
                 BaseUomId = uom.UomId,
                 StockNature = StockNature.Stocked,
                 TrackingMode = TrackingMode.None,
-                SalePrice = 50m,
+                SellingFlatPrice = 50m,
                 ContentQty = 500m,
                 ContentUnit = MeasureUnit.Ml,
                 ContentBaseQty = 500m,
@@ -445,7 +479,7 @@ public static class DataSeeder
                     ItemId = items[0].ItemId,
                     WarehouseId = warehouse.WarehouseId,
                     Qty = 1m,
-                    UnitPrice = items[0].SalePrice.GetValueOrDefault(),
+                    UnitPrice = items[0].SellingFlatPrice.GetValueOrDefault(),
                     IncludeInBundle = true,
                     SortOrder = 1
                 },
@@ -454,7 +488,7 @@ public static class DataSeeder
                     ItemId = items[1].ItemId,
                     WarehouseId = warehouse.WarehouseId,
                     Qty = 1m,
-                    UnitPrice = items[1].SalePrice.GetValueOrDefault(),
+                    UnitPrice = items[1].SellingFlatPrice.GetValueOrDefault(),
                     IncludeInBundle = true,
                     SortOrder = 2
                 }
@@ -478,10 +512,10 @@ public static class DataSeeder
                 BundleName = "Demo Bundle Draft",
                 BundleCode = "BND-DEMO-001",
                 Status = BundleSaleStatus.Draft,
-                ComponentSubtotal = items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault(),
+                ComponentSubtotal = items[0].SellingFlatPrice.GetValueOrDefault() + items[1].SellingFlatPrice.GetValueOrDefault(),
                 BundlePrice = 0m,
-                MarginAmount = -(items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault()),
+                MarginAmount = -(items[0].SellingFlatPrice.GetValueOrDefault() + items[1].SellingFlatPrice.GetValueOrDefault()),
-                DiscountTotal = items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault(),
+                DiscountTotal = items[0].SellingFlatPrice.GetValueOrDefault() + items[1].SellingFlatPrice.GetValueOrDefault(),
                 TaxTotal = 0m,
                 GrandTotal = 0m,
                 CreatedAt = now.AddDays(-2),
@@ -493,8 +527,8 @@ public static class DataSeeder
                         Description = items[0].Name,
                         Qty = 1m,
                         WarehouseId = warehouse.WarehouseId,
-                        UnitPrice = items[0].SalePrice.GetValueOrDefault(),
+                        UnitPrice = items[0].SellingFlatPrice.GetValueOrDefault(),
-                        LineTotal = items[0].SalePrice.GetValueOrDefault(),
+                        LineTotal = items[0].SellingFlatPrice.GetValueOrDefault(),
                         IncludeInBundle = true,
                         IsComponent = true
                     },
@@ -504,8 +538,8 @@ public static class DataSeeder
                         Description = items[1].Name,
                         Qty = 1m,
                         WarehouseId = warehouse.WarehouseId,
-                        UnitPrice = items[1].SalePrice.GetValueOrDefault(),
+                        UnitPrice = items[1].SellingFlatPrice.GetValueOrDefault(),
-                        LineTotal = items[1].SalePrice.GetValueOrDefault(),
+                        LineTotal = items[1].SellingFlatPrice.GetValueOrDefault(),
                         IncludeInBundle = true,
                         IsComponent = true
                     }
@@ -523,12 +557,12 @@ public static class DataSeeder
                 BundleName = "Demo Bundle Posted",
                 BundleCode = "BND-DEMO-001",
                 Status = BundleSaleStatus.Posted,
-                ComponentSubtotal = items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault(),
+                ComponentSubtotal = items[0].SellingFlatPrice.GetValueOrDefault() + items[1].SellingFlatPrice.GetValueOrDefault(),
-                BundlePrice = (items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault()) - 10m,
+                BundlePrice = (items[0].SellingFlatPrice.GetValueOrDefault() + items[1].SellingFlatPrice.GetValueOrDefault()) - 10m,
                 MarginAmount = -10m,
                 DiscountTotal = 10m,
                 TaxTotal = 0m,
-                GrandTotal = (items[0].SalePrice.GetValueOrDefault() + items[1].SalePrice.GetValueOrDefault()) - 10m,
+                GrandTotal = (items[0].SellingFlatPrice.GetValueOrDefault() + items[1].SellingFlatPrice.GetValueOrDefault()) - 10m,
                 CreatedAt = now.AddDays(-1),
                 UpdatedAt = now.AddHours(-2),
                 Lines =
@@ -539,8 +573,8 @@ public static class DataSeeder
                         Description = items[0].Name,
                         Qty = 1m,
                         WarehouseId = warehouse.WarehouseId,
-                        UnitPrice = items[0].SalePrice.GetValueOrDefault(),
+                        UnitPrice = items[0].SellingFlatPrice.GetValueOrDefault(),
-                        LineTotal = items[0].SalePrice.GetValueOrDefault(),
+                        LineTotal = items[0].SellingFlatPrice.GetValueOrDefault(),
                         IncludeInBundle = true,
                         IsComponent = true
                     },
@@ -550,8 +584,8 @@ public static class DataSeeder
                         Description = items[1].Name,
                         Qty = 1m,
                         WarehouseId = warehouse.WarehouseId,
-                        UnitPrice = items[1].SalePrice.GetValueOrDefault(),
+                        UnitPrice = items[1].SellingFlatPrice.GetValueOrDefault(),
-                        LineTotal = items[1].SalePrice.GetValueOrDefault(),
+                        LineTotal = items[1].SellingFlatPrice.GetValueOrDefault(),
                         IncludeInBundle = true,
                         IsComponent = true
                     }
@@ -569,12 +603,12 @@ public static class DataSeeder
                 BundleName = "Demo Bundle Cancelled",
                 BundleCode = "BND-DEMO-001",
                 Status = BundleSaleStatus.Cancelled,
-                ComponentSubtotal = items[0].SalePrice.GetValueOrDefault(),
+                ComponentSubtotal = items[0].SellingFlatPrice.GetValueOrDefault(),
-                BundlePrice = items[0].SalePrice.GetValueOrDefault(),
+                BundlePrice = items[0].SellingFlatPrice.GetValueOrDefault(),
                 MarginAmount = 0m,
                 DiscountTotal = 0m,
                 TaxTotal = 0m,
-                GrandTotal = items[0].SalePrice.GetValueOrDefault(),
+                GrandTotal = items[0].SellingFlatPrice.GetValueOrDefault(),
                 CreatedAt = now,
                 UpdatedAt = now,
                 Lines =
@@ -585,8 +619,8 @@ public static class DataSeeder
                         Description = items[0].Name,
                         Qty = 1m,
                         WarehouseId = secondaryWarehouse.WarehouseId,
-                        UnitPrice = items[0].SalePrice.GetValueOrDefault(),
+                        UnitPrice = items[0].SellingFlatPrice.GetValueOrDefault(),
-                        LineTotal = items[0].SalePrice.GetValueOrDefault(),
+                        LineTotal = items[0].SellingFlatPrice.GetValueOrDefault(),
                         IncludeInBundle = true,
                         IsComponent = true
                     }

Backend/ERPCore/Infra/Persistence/ErpDbContext.cs

@@ -38,6 +38,11 @@ public class ErpDbContext : DbContext
     
     /// <summary>Singleton row (FR-MD-11).</summary>
     public DbSet<ProductConfig> ProductConfig => Set<ProductConfig>();
+    /// <summary>Singleton row gating whether this deployment uses branches at all.</summary>
+    public DbSet<BranchConfig> BranchConfig => Set<BranchConfig>();
+    /// <summary>Singleton row for notification delivery preferences.</summary>
+    public DbSet<NotificationConfig> NotificationConfig => Set<NotificationConfig>();
+    public DbSet<NotificationConfigModule> NotificationConfigModules => Set<NotificationConfigModule>();
 
     // --- Cross-cutting (docs/10 Part C.7) ---
     public DbSet<User> Users => Set<User>();
@@ -63,7 +68,11 @@ public class ErpDbContext : DbContext
     // --- Goods Receipt (docs/10 Part C.3) ---
     public DbSet<Grn> Grns => Set<Grn>();
     public DbSet<GrnLine> GrnLines => Set<GrnLine>();
-    public DbSet<GrnPayment> GrnPayments => Set<GrnPayment>();
+
+    // --- Purchase Invoices (vendor invoices consolidating Confirmed GRNs) ---
+    public DbSet<PurchaseInvoice> PurchaseInvoices => Set<PurchaseInvoice>();
+    public DbSet<PurchaseInvoiceLine> PurchaseInvoiceLines => Set<PurchaseInvoiceLine>();
+    public DbSet<PurchaseInvoicePayment> PurchaseInvoicePayments => Set<PurchaseInvoicePayment>();
 
     // --- Batch / Serial (docs/10 Part C.4) ---
     public DbSet<Batch> Batches => Set<Batch>();

Backend/ERPCore/Migrations/20260818090139_AddProductionNavPermissions.cs

@@ -0,0 +1,90 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+#pragma warning disable CA1814 // Prefer jagged arrays over multidimensional
+
+namespace ERPCore.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddProductionNavPermissions : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.InsertData(
+                table: "nav_items",
+                columns: new[] { "NavItemId", "Code", "Href", "Icon", "Label", "SortOrder" },
+                values: new object[] { 14, "production", "/dashboard/production", null, "Production", 14 });
+
+            migrationBuilder.InsertData(
+                table: "permissions",
+                columns: new[] { "PermissionId", "Code", "NavItemId", "SubNavItemId" },
+                values: new object[] { 35, "NAV:production", 14, null });
+
+            migrationBuilder.InsertData(
+                table: "sub_nav_items",
+                columns: new[] { "SubNavItemId", "Code", "Href", "Icon", "Label", "NavItemId", "SortOrder" },
+                values: new object[,]
+                {
+                    { 24, "production.templates", "/dashboard/production/templates", null, "Templates", 14, 1 },
+                    { 25, "production.runs", "/dashboard/production/runs", null, "Runs", 14, 2 },
+                    { 26, "production.produced", "/dashboard/production/produced", null, "Produced", 14, 3 }
+                });
+
+            migrationBuilder.InsertData(
+                table: "permissions",
+                columns: new[] { "PermissionId", "Code", "NavItemId", "SubNavItemId" },
+                values: new object[,]
+                {
+                    { 36, "NAV:production.templates", null, 24 },
+                    { 37, "NAV:production.runs", null, 25 },
+                    { 38, "NAV:production.produced", null, 26 }
+                });
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DeleteData(
+                table: "permissions",
+                keyColumn: "PermissionId",
+                keyValue: 35);
+
+            migrationBuilder.DeleteData(
+                table: "permissions",
+                keyColumn: "PermissionId",
+                keyValue: 36);
+
+            migrationBuilder.DeleteData(
+                table: "permissions",
+                keyColumn: "PermissionId",
+                keyValue: 37);
+
+            migrationBuilder.DeleteData(
+                table: "permissions",
+                keyColumn: "PermissionId",
+                keyValue: 38);
+
+            migrationBuilder.DeleteData(
+                table: "sub_nav_items",
+                keyColumn: "SubNavItemId",
+                keyValue: 24);
+
+            migrationBuilder.DeleteData(
+                table: "sub_nav_items",
+                keyColumn: "SubNavItemId",
+                keyValue: 25);
+
+            migrationBuilder.DeleteData(
+                table: "sub_nav_items",
+                keyColumn: "SubNavItemId",
+                keyValue: 26);
+
+            migrationBuilder.DeleteData(
+                table: "nav_items",
+                keyColumn: "NavItemId",
+                keyValue: 14);
+        }
+    }
+}

Backend/ERPCore/Migrations/20260820083810_itemModel.cs

@@ -0,0 +1,52 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ERPCore.Migrations
+{
+    /// <inheritdoc />
+    public partial class itemModel : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.RenameColumn(
+                name: "SalePrice",
+                table: "items",
+                newName: "SellingMinPrice");
+
+            migrationBuilder.AddColumn<decimal>(
+                name: "SellingFlatPrice",
+                table: "items",
+                type: "numeric(18,4)",
+                precision: 18,
+                scale: 4,
+                nullable: true);
+
+            migrationBuilder.AddColumn<decimal>(
+                name: "SellingMaxPrice",
+                table: "items",
+                type: "numeric(18,4)",
+                precision: 18,
+                scale: 4,
+                nullable: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropColumn(
+                name: "SellingFlatPrice",
+                table: "items");
+
+            migrationBuilder.DropColumn(
+                name: "SellingMaxPrice",
+                table: "items");
+
+            migrationBuilder.RenameColumn(
+                name: "SellingMinPrice",
+                table: "items",
+                newName: "SalePrice");
+        }
+    }
+}

Backend/ERPCore/Migrations/20260820100345_AddNotificationConfigModulePreferences.cs

@@ -0,0 +1,103 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+
+#nullable disable
+
+namespace ERPCore.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddNotificationConfigModulePreferences : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "notification_config",
+                columns: table => new
+                {
+                    NotificationConfigId = table.Column<int>(type: "integer", nullable: false),
+                    UpdatedAt = table.Column<DateTime>(type: "timestamp with time zone", nullable: true),
+                    UpdatedBy = table.Column<int>(type: "integer", nullable: true),
+                    xmin = table.Column<uint>(type: "xid", rowVersion: true, nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_notification_config", x => x.NotificationConfigId);
+                    table.CheckConstraint("ck_notification_config_singleton", "\"NotificationConfigId\" = 1");
+                    table.ForeignKey(
+                        name: "FK_notification_config_users_UpdatedBy",
+                        column: x => x.UpdatedBy,
+                        principalTable: "users",
+                        principalColumn: "UserId",
+                        onDelete: ReferentialAction.Restrict);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "notification_config_modules",
+                columns: table => new
+                {
+                    NotificationConfigModuleId = table.Column<int>(type: "integer", nullable: false)
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    NotificationConfigId = table.Column<int>(type: "integer", nullable: false),
+                    ModuleKey = table.Column<string>(type: "character varying(100)", maxLength: 100, nullable: false),
+                    EmailEnabled = table.Column<bool>(type: "boolean", nullable: false, defaultValue: false),
+                    SmsEnabled = table.Column<bool>(type: "boolean", nullable: false, defaultValue: false),
+                    InAppEnabled = table.Column<bool>(type: "boolean", nullable: false, defaultValue: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_notification_config_modules", x => x.NotificationConfigModuleId);
+                    table.ForeignKey(
+                        name: "FK_notification_config_modules_notification_config_Notificatio~",
+                        column: x => x.NotificationConfigId,
+                        principalTable: "notification_config",
+                        principalColumn: "NotificationConfigId",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.Sql("""
+                INSERT INTO sub_nav_items ("SubNavItemId", "NavItemId", "Code", "Href", "Icon", "Label", "SortOrder")
+                VALUES (24, 9, 'settings.notification-config', '/dashboard/settings/notification-config', NULL, 'Notification Config', 3)
+                ON CONFLICT ("SubNavItemId") DO UPDATE
+                SET "NavItemId" = EXCLUDED."NavItemId",
+                    "Code" = EXCLUDED."Code",
+                    "Href" = EXCLUDED."Href",
+                    "Icon" = EXCLUDED."Icon",
+                    "Label" = EXCLUDED."Label",
+                    "SortOrder" = EXCLUDED."SortOrder";
+                """);
+
+            migrationBuilder.CreateIndex(
+                name: "IX_notification_config_UpdatedBy",
+                table: "notification_config",
+                column: "UpdatedBy");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_notification_config_modules_ModuleKey",
+                table: "notification_config_modules",
+                column: "ModuleKey",
+                unique: true);
+
+            migrationBuilder.CreateIndex(
+                name: "IX_notification_config_modules_NotificationConfigId",
+                table: "notification_config_modules",
+                column: "NotificationConfigId");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "notification_config_modules");
+
+            migrationBuilder.DropTable(
+                name: "notification_config");
+
+            migrationBuilder.DeleteData(
+                table: "sub_nav_items",
+                keyColumn: "SubNavItemId",
+                keyValue: 24);
+        }
+    }
+}

Backend/ERPCore/Migrations/20260820120000_UpdateItemSellingPrices.cs

@@ -0,0 +1,49 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ERPCore.Migrations
+{
+    public partial class UpdateItemSellingPrices : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.RenameColumn(
+                name: "SalePrice",
+                table: "items",
+                newName: "SellingFlatPrice");
+
+            migrationBuilder.AddColumn<decimal>(
+                name: "SellingMinPrice",
+                table: "items",
+                type: "numeric(18,4)",
+                precision: 18,
+                scale: 4,
+                nullable: true);
+
+            migrationBuilder.AddColumn<decimal>(
+                name: "SellingMaxPrice",
+                table: "items",
+                type: "numeric(18,4)",
+                precision: 18,
+                scale: 4,
+                nullable: true);
+        }
+
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropColumn(
+                name: "SellingMinPrice",
+                table: "items");
+
+            migrationBuilder.DropColumn(
+                name: "SellingMaxPrice",
+                table: "items");
+
+            migrationBuilder.RenameColumn(
+                name: "SellingFlatPrice",
+                table: "items",
+                newName: "SalePrice");
+        }
+    }
+}

Backend/ERPCore/Migrations/20260820125724_AddProductConfigFeatureFlags.cs

@@ -0,0 +1,62 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ERPCore.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddProductConfigFeatureFlags : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<bool>(
+                name: "BatchListsEnabled",
+                table: "product_config",
+                type: "boolean",
+                nullable: false,
+                defaultValue: true);
+
+            migrationBuilder.AddColumn<bool>(
+                name: "SellingPricesEnabled",
+                table: "product_config",
+                type: "boolean",
+                nullable: false,
+                defaultValue: true);
+
+            migrationBuilder.AddColumn<bool>(
+                name: "SerialNumbersEnabled",
+                table: "product_config",
+                type: "boolean",
+                nullable: false,
+                defaultValue: true);
+
+            migrationBuilder.AddColumn<bool>(
+                name: "WarrantyPeriodsEnabled",
+                table: "product_config",
+                type: "boolean",
+                nullable: false,
+                defaultValue: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropColumn(
+                name: "BatchListsEnabled",
+                table: "product_config");
+
+            migrationBuilder.DropColumn(
+                name: "SellingPricesEnabled",
+                table: "product_config");
+
+            migrationBuilder.DropColumn(
+                name: "SerialNumbersEnabled",
+                table: "product_config");
+
+            migrationBuilder.DropColumn(
+                name: "WarrantyPeriodsEnabled",
+                table: "product_config");
+        }
+    }
+}

Backend/ERPCore/Migrations/20260825000000_FixProductionTemplatesSubNavItemIdConflict.Designer.cs

@@ -0,0 +1,24 @@
+// <auto-generated />
+using ERPCore.Infra.Persistence;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ERPCore.Migrations
+{
+    [DbContext(typeof(ErpDbContext))]
+    [Migration("20260825000000_FixProductionTemplatesSubNavItemIdConflict")]
+    partial class FixProductionTemplatesSubNavItemIdConflict
+    {
+        /// <inheritdoc />
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+            // This migration only repairs seed row data via raw SQL — no entity/column shape
+            // changes — so it does not redeclare the full model here. The single source of
+            // truth for scaffolding future migrations is ErpDbContextModelSnapshot.cs, which
+            // already reflects this fix (production.templates seeded at SubNavItemId 27).
+        }
+    }
+}

Backend/ERPCore/Migrations/20260825000000_FixProductionTemplatesSubNavItemIdConflict.cs

@@ -0,0 +1,46 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ERPCore.Migrations
+{
+    /// <summary>
+    /// Repairs a collision baked into migration history: 20260818090139_AddProductionNavPermissions
+    /// inserted "production.templates" as sub_nav_items row 24, then
+    /// 20260820100345_AddNotificationConfigModulePreferences reused the same literal id 24 for
+    /// "settings.notification-config" via a raw-SQL <c>INSERT ... ON CONFLICT ("SubNavItemId") DO
+    /// UPDATE</c>, silently overwriting the production.templates row instead of inserting a new
+    /// one. Row 24 now correctly holds notification-config; this migration re-creates the lost
+    /// production.templates row under a fresh id (27, matching the corrected seed data in
+    /// SubNavItemConfiguration/PermissionConfiguration) and repoints the NAV:production.templates
+    /// permission (id 36) at it.
+    /// </summary>
+    public partial class FixProductionTemplatesSubNavItemIdConflict : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.Sql("""
+                INSERT INTO sub_nav_items ("SubNavItemId", "NavItemId", "Code", "Href", "Icon", "Label", "SortOrder")
+                VALUES (27, 14, 'production.templates', '/dashboard/production/templates', NULL, 'Templates', 1)
+                ON CONFLICT ("SubNavItemId") DO NOTHING;
+                """);
+
+            migrationBuilder.Sql("""
+                UPDATE permissions SET "SubNavItemId" = 27 WHERE "PermissionId" = 36;
+                """);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.Sql("""
+                UPDATE permissions SET "SubNavItemId" = 24 WHERE "PermissionId" = 36;
+                """);
+
+            migrationBuilder.Sql("""
+                DELETE FROM sub_nav_items WHERE "SubNavItemId" = 27;
+                """);
+        }
+    }
+}

Backend/ERPCore/Migrations/20260831060800_AddPurchaseInvoices.cs

@@ -0,0 +1,303 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+
+#nullable disable
+
+namespace ERPCore.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddPurchaseInvoices : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "grn_payments");
+
+            migrationBuilder.DropColumn(
+                name: "BalanceAmount",
+                table: "grns");
+
+            migrationBuilder.DropColumn(
+                name: "PaidAmount",
+                table: "grns");
+
+            migrationBuilder.AddColumn<int>(
+                name: "PurchaseInvoiceId",
+                table: "grns",
+                type: "integer",
+                nullable: true);
+
+            migrationBuilder.CreateTable(
+                name: "purchase_invoices",
+                columns: table => new
+                {
+                    PurchaseInvoiceId = table.Column<int>(type: "integer", nullable: false)
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    DocNo = table.Column<string>(type: "character varying(30)", maxLength: 30, nullable: false),
+                    VendorInvoiceNo = table.Column<string>(type: "character varying(50)", maxLength: 50, nullable: false),
+                    VendorInvoiceDate = table.Column<DateTime>(type: "timestamp with time zone", nullable: false),
+                    VendorId = table.Column<int>(type: "integer", nullable: false),
+                    VendorSnapshotName = table.Column<string>(type: "character varying(200)", maxLength: 200, nullable: false),
+                    VendorSnapshotTaxNo = table.Column<string>(type: "character varying(50)", maxLength: 50, nullable: true),
+                    Status = table.Column<string>(type: "character varying(20)", maxLength: 20, nullable: false, defaultValue: "Draft"),
+                    Subtotal = table.Column<decimal>(type: "numeric(18,4)", precision: 18, scale: 4, nullable: false),
+                    VatTotal = table.Column<decimal>(type: "numeric(18,4)", precision: 18, scale: 4, nullable: false),
+                    GrandTotal = table.Column<decimal>(type: "numeric(18,4)", precision: 18, scale: 4, nullable: false),
+                    PaidAmount = table.Column<decimal>(type: "numeric(18,4)", precision: 18, scale: 4, nullable: false),
+                    BalanceAmount = table.Column<decimal>(type: "numeric(18,4)", precision: 18, scale: 4, nullable: false),
+                    GlJournalNo = table.Column<string>(type: "character varying(30)", maxLength: 30, nullable: true),
+                    GlPostedAt = table.Column<DateTime>(type: "timestamp with time zone", nullable: true),
+                    CreatedBy = table.Column<int>(type: "integer", nullable: false),
+                    CreatedAt = table.Column<DateTime>(type: "timestamp with time zone", nullable: false),
+                    UpdatedAt = table.Column<DateTime>(type: "timestamp with time zone", nullable: true),
+                    xmin = table.Column<uint>(type: "xid", rowVersion: true, nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_purchase_invoices", x => x.PurchaseInvoiceId);
+                    table.ForeignKey(
+                        name: "FK_purchase_invoices_users_CreatedBy",
+                        column: x => x.CreatedBy,
+                        principalTable: "users",
+                        principalColumn: "UserId",
+                        onDelete: ReferentialAction.Restrict);
+                    table.ForeignKey(
+                        name: "FK_purchase_invoices_vendors_VendorId",
+                        column: x => x.VendorId,
+                        principalTable: "vendors",
+                        principalColumn: "VendorId",
+                        onDelete: ReferentialAction.Restrict);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "purchase_invoice_lines",
+                columns: table => new
+                {
+                    PurchaseInvoiceLineId = table.Column<int>(type: "integer", nullable: false)
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    PurchaseInvoiceId = table.Column<int>(type: "integer", nullable: false),
+                    GrnId = table.Column<int>(type: "integer", nullable: false),
+                    Subtotal = table.Column<decimal>(type: "numeric(18,4)", precision: 18, scale: 4, nullable: false),
+                    VatTotal = table.Column<decimal>(type: "numeric(18,4)", precision: 18, scale: 4, nullable: false),
+                    LineTotal = table.Column<decimal>(type: "numeric(18,4)", precision: 18, scale: 4, nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_purchase_invoice_lines", x => x.PurchaseInvoiceLineId);
+                    table.ForeignKey(
+                        name: "FK_purchase_invoice_lines_grns_GrnId",
+                        column: x => x.GrnId,
+                        principalTable: "grns",
+                        principalColumn: "GrnId",
+                        onDelete: ReferentialAction.Restrict);
+                    table.ForeignKey(
+                        name: "FK_purchase_invoice_lines_purchase_invoices_PurchaseInvoiceId",
+                        column: x => x.PurchaseInvoiceId,
+                        principalTable: "purchase_invoices",
+                        principalColumn: "PurchaseInvoiceId",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "purchase_invoice_payments",
+                columns: table => new
+                {
+                    PurchaseInvoicePaymentId = table.Column<int>(type: "integer", nullable: false)
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    PurchaseInvoiceId = table.Column<int>(type: "integer", nullable: false),
+                    Amount = table.Column<decimal>(type: "numeric(18,4)", precision: 18, scale: 4, nullable: false),
+                    PaymentDate = table.Column<DateTime>(type: "timestamp with time zone", nullable: false),
+                    GlBankAccountId = table.Column<long>(type: "bigint", nullable: false),
+                    BankAccountName = table.Column<string>(type: "character varying(200)", maxLength: 200, nullable: false),
+                    Reference = table.Column<string>(type: "character varying(100)", maxLength: 100, nullable: true),
+                    GlJournalNo = table.Column<string>(type: "character varying(30)", maxLength: 30, nullable: true),
+                    CreatedBy = table.Column<int>(type: "integer", nullable: false),
+                    CreatedAt = table.Column<DateTime>(type: "timestamp with time zone", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_purchase_invoice_payments", x => x.PurchaseInvoicePaymentId);
+                    table.ForeignKey(
+                        name: "FK_purchase_invoice_payments_purchase_invoices_PurchaseInvoice~",
+                        column: x => x.PurchaseInvoiceId,
+                        principalTable: "purchase_invoices",
+                        principalColumn: "PurchaseInvoiceId",
+                        onDelete: ReferentialAction.Restrict);
+                    table.ForeignKey(
+                        name: "FK_purchase_invoice_payments_users_CreatedBy",
+                        column: x => x.CreatedBy,
+                        principalTable: "users",
+                        principalColumn: "UserId",
+                        onDelete: ReferentialAction.Restrict);
+                });
+
+            migrationBuilder.InsertData(
+                table: "sub_nav_items",
+                columns: new[] { "SubNavItemId", "Code", "Href", "Icon", "Label", "NavItemId", "SortOrder" },
+                values: new object[] { 28, "procurement.purchase-invoices", "/dashboard/procurement/purchase-invoices", null, "Purchase Invoices", 4, 5 });
+
+            migrationBuilder.InsertData(
+                table: "permissions",
+                columns: new[] { "PermissionId", "Code", "NavItemId", "SubNavItemId" },
+                values: new object[] { 39, "NAV:procurement.purchase-invoices", null, 28 });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_grns_PurchaseInvoiceId",
+                table: "grns",
+                column: "PurchaseInvoiceId");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_purchase_invoice_lines_GrnId",
+                table: "purchase_invoice_lines",
+                column: "GrnId",
+                unique: true);
+
+            migrationBuilder.CreateIndex(
+                name: "IX_purchase_invoice_lines_PurchaseInvoiceId",
+                table: "purchase_invoice_lines",
+                column: "PurchaseInvoiceId");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_purchase_invoice_payments_CreatedBy",
+                table: "purchase_invoice_payments",
+                column: "CreatedBy");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_purchase_invoice_payments_PurchaseInvoiceId",
+                table: "purchase_invoice_payments",
+                column: "PurchaseInvoiceId");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_purchase_invoices_CreatedBy",
+                table: "purchase_invoices",
+                column: "CreatedBy");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_purchase_invoices_DocNo",
+                table: "purchase_invoices",
+                column: "DocNo",
+                unique: true);
+
+            migrationBuilder.CreateIndex(
+                name: "IX_purchase_invoices_Status",
+                table: "purchase_invoices",
+                column: "Status");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_purchase_invoices_VendorId",
+                table: "purchase_invoices",
+                column: "VendorId");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_purchase_invoices_VendorId_VendorInvoiceNo",
+                table: "purchase_invoices",
+                columns: new[] { "VendorId", "VendorInvoiceNo" });
+
+            migrationBuilder.AddForeignKey(
+                name: "FK_grns_purchase_invoices_PurchaseInvoiceId",
+                table: "grns",
+                column: "PurchaseInvoiceId",
+                principalTable: "purchase_invoices",
+                principalColumn: "PurchaseInvoiceId",
+                onDelete: ReferentialAction.Restrict);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropForeignKey(
+                name: "FK_grns_purchase_invoices_PurchaseInvoiceId",
+                table: "grns");
+
+            migrationBuilder.DropTable(
+                name: "purchase_invoice_lines");
+
+            migrationBuilder.DropTable(
+                name: "purchase_invoice_payments");
+
+            migrationBuilder.DropTable(
+                name: "purchase_invoices");
+
+            migrationBuilder.DropIndex(
+                name: "IX_grns_PurchaseInvoiceId",
+                table: "grns");
+
+            migrationBuilder.DeleteData(
+                table: "permissions",
+                keyColumn: "PermissionId",
+                keyValue: 39);
+
+            migrationBuilder.DeleteData(
+                table: "sub_nav_items",
+                keyColumn: "SubNavItemId",
+                keyValue: 28);
+
+            migrationBuilder.DropColumn(
+                name: "PurchaseInvoiceId",
+                table: "grns");
+
+            migrationBuilder.AddColumn<decimal>(
+                name: "BalanceAmount",
+                table: "grns",
+                type: "numeric(18,4)",
+                precision: 18,
+                scale: 4,
+                nullable: false,
+                defaultValue: 0m);
+
+            migrationBuilder.AddColumn<decimal>(
+                name: "PaidAmount",
+                table: "grns",
+                type: "numeric(18,4)",
+                precision: 18,
+                scale: 4,
+                nullable: false,
+                defaultValue: 0m);
+
+            migrationBuilder.CreateTable(
+                name: "grn_payments",
+                columns: table => new
+                {
+                    GrnPaymentId = table.Column<int>(type: "integer", nullable: false)
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    CreatedBy = table.Column<int>(type: "integer", nullable: false),
+                    GrnId = table.Column<int>(type: "integer", nullable: false),
+                    Amount = table.Column<decimal>(type: "numeric(18,4)", precision: 18, scale: 4, nullable: false),
+                    BankAccountName = table.Column<string>(type: "character varying(200)", maxLength: 200, nullable: false),
+                    CreatedAt = table.Column<DateTime>(type: "timestamp with time zone", nullable: false),
+                    GlBankAccountId = table.Column<long>(type: "bigint", nullable: false),
+                    GlJournalNo = table.Column<string>(type: "character varying(30)", maxLength: 30, nullable: true),
+                    PaymentDate = table.Column<DateTime>(type: "timestamp with time zone", nullable: false),
+                    Reference = table.Column<string>(type: "character varying(100)", maxLength: 100, nullable: true)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_grn_payments", x => x.GrnPaymentId);
+                    table.ForeignKey(
+                        name: "FK_grn_payments_grns_GrnId",
+                        column: x => x.GrnId,
+                        principalTable: "grns",
+                        principalColumn: "GrnId",
+                        onDelete: ReferentialAction.Restrict);
+                    table.ForeignKey(
+                        name: "FK_grn_payments_users_CreatedBy",
+                        column: x => x.CreatedBy,
+                        principalTable: "users",
+                        principalColumn: "UserId",
+                        onDelete: ReferentialAction.Restrict);
+                });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_grn_payments_CreatedBy",
+                table: "grn_payments",
+                column: "CreatedBy");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_grn_payments_GrnId",
+                table: "grn_payments",
+                column: "GrnId");
+        }
+    }
+}

Backend/ERPCore/Migrations/20260901104702_AddBranchPhoneNumberAndCodeAutogen.cs

@@ -0,0 +1,29 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ERPCore.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddBranchPhoneNumberAndCodeAutogen : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<string>(
+                name: "PhoneNumber",
+                table: "hr_branches",
+                type: "character varying(30)",
+                maxLength: 30,
+                nullable: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropColumn(
+                name: "PhoneNumber",
+                table: "hr_branches");
+        }
+    }
+}

Backend/ERPCore/Migrations/20260901120000_AddSettingsBranchesNavItem.cs

@@ -0,0 +1,38 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ERPCore.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddSettingsBranchesNavItem : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.InsertData(
+                table: "sub_nav_items",
+                columns: new[] { "SubNavItemId", "Code", "Href", "Icon", "Label", "NavItemId", "SortOrder" },
+                values: new object[] { 29, "settings.branches", "/dashboard/settings/branches", null, "Branches", 9, 0 });
+
+            migrationBuilder.InsertData(
+                table: "permissions",
+                columns: new[] { "PermissionId", "Code", "NavItemId", "SubNavItemId" },
+                values: new object[] { 40, "NAV:settings.branches", null, 29 });
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DeleteData(
+                table: "permissions",
+                keyColumn: "PermissionId",
+                keyValue: 40);
+
+            migrationBuilder.DeleteData(
+                table: "sub_nav_items",
+                keyColumn: "SubNavItemId",
+                keyValue: 29);
+        }
+    }
+}

Backend/ERPCore/Migrations/20260902055505_MakeEmployeeBranchRequired.cs

@@ -0,0 +1,50 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ERPCore.Migrations
+{
+    /// <inheritdoc />
+    public partial class MakeEmployeeBranchRequired : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            // Branch becomes a required field on Employee going forward. Any pre-existing
+            // employee left with no branch is backfilled to a "Main Branch" placeholder
+            // (created only if it doesn't already exist) so the NOT NULL below never fails
+            // on live data.
+            migrationBuilder.Sql(@"
+                INSERT INTO hr_branches (""Code"", ""Name"", ""Status"", ""CreatedAt"")
+                SELECT 'BR-000', 'Main Branch', 'Active', now()
+                WHERE NOT EXISTS (SELECT 1 FROM hr_branches WHERE ""Code"" = 'BR-000')
+                  AND EXISTS (SELECT 1 FROM hr_employees WHERE ""BranchId"" IS NULL);
+
+                UPDATE hr_employees
+                SET ""BranchId"" = (SELECT ""BranchId"" FROM hr_branches WHERE ""Code"" = 'BR-000')
+                WHERE ""BranchId"" IS NULL;
+            ");
+
+            migrationBuilder.AlterColumn<int>(
+                name: "BranchId",
+                table: "hr_employees",
+                type: "integer",
+                nullable: false,
+                oldClrType: typeof(int),
+                oldType: "integer",
+                oldNullable: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AlterColumn<int>(
+                name: "BranchId",
+                table: "hr_employees",
+                type: "integer",
+                nullable: true,
+                oldClrType: typeof(int),
+                oldType: "integer");
+        }
+    }
+}

Backend/ERPCore/Migrations/20260902094609_AddWarehouseBranch.cs

@@ -0,0 +1,73 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ERPCore.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddWarehouseBranch : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<int>(
+                name: "BranchId",
+                table: "warehouses",
+                type: "integer",
+                nullable: true);
+
+            // Backfill any pre-existing warehouse onto the same "Main Branch" placeholder
+            // used by the earlier MakeEmployeeBranchRequired migration (created only if it
+            // doesn't already exist) — keeps a single de-facto default rather than minting
+            // a second one — before the column is locked to NOT NULL below.
+            migrationBuilder.Sql(@"
+                INSERT INTO hr_branches (""Code"", ""Name"", ""Status"", ""CreatedAt"")
+                SELECT 'BR-000', 'Main Branch', 'Active', now()
+                WHERE NOT EXISTS (SELECT 1 FROM hr_branches WHERE ""Code"" = 'BR-000')
+                  AND EXISTS (SELECT 1 FROM warehouses WHERE ""BranchId"" IS NULL);
+
+                UPDATE warehouses
+                SET ""BranchId"" = (SELECT ""BranchId"" FROM hr_branches WHERE ""Code"" = 'BR-000')
+                WHERE ""BranchId"" IS NULL;
+            ");
+
+            migrationBuilder.AlterColumn<int>(
+                name: "BranchId",
+                table: "warehouses",
+                type: "integer",
+                nullable: false,
+                oldClrType: typeof(int),
+                oldType: "integer",
+                oldNullable: true);
+
+            migrationBuilder.CreateIndex(
+                name: "IX_warehouses_BranchId",
+                table: "warehouses",
+                column: "BranchId");
+
+            migrationBuilder.AddForeignKey(
+                name: "FK_warehouses_hr_branches_BranchId",
+                table: "warehouses",
+                column: "BranchId",
+                principalTable: "hr_branches",
+                principalColumn: "BranchId",
+                onDelete: ReferentialAction.Restrict);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropForeignKey(
+                name: "FK_warehouses_hr_branches_BranchId",
+                table: "warehouses");
+
+            migrationBuilder.DropIndex(
+                name: "IX_warehouses_BranchId",
+                table: "warehouses");
+
+            migrationBuilder.DropColumn(
+                name: "BranchId",
+                table: "warehouses");
+        }
+    }
+}