feat: add ItemOverviewDto for enriched item data in items list

feat: implement CustomerDetailPage for detailed customer view and editing

feat: create CustomersPage for listing and managing customers with filters

feat: add ColumnsMenu component for customizable table columns visibility

feat: implement CSV export functionality for data download

feat: add customer code generation logic for unique customer identifiers

Backend/ERPCore/Controllers/ItemsController.cs

@@ -30,6 +30,19 @@ public sealed class ItemsController : ApiControllerBase
         CancellationToken ct)
         => Ok(await _items.ListAsync(query, status, categoryId, subCategoryId, brandId, trackingMode, ct));
 
+    /// <summary>Items list enriched with stock value, low-stock, last-purchase and
+    /// trailing-30-day sales aggregates, for the Items overview table.</summary>
+    [HttpGet("overview")]
+    [ProducesResponseType(typeof(PagedResponse<ItemOverviewDto>), StatusCodes.Status200OK)]
+    public async Task<ActionResult<PagedResponse<ItemOverviewDto>>> Overview(
+        [FromQuery] PageQuery query,
+        [FromQuery] EntityStatus? status,
+        [FromQuery] int? categoryId,
+        [FromQuery] int? subCategoryId,
+        [FromQuery] int? brandId,
+        CancellationToken ct)
+        => Ok(await _items.GetOverviewAsync(query, status, categoryId, subCategoryId, brandId, ct));
+
     /// <summary>Barcode/RFID lookup — matches an item's barcode/SKU, or a batch/serial
     /// barcode/no (optionally scoped to <paramref name="itemId"/> first).</summary>
     [HttpGet("scan")]

Backend/ERPCore/Dtos/Grn/GrnDtos.cs

@@ -22,7 +22,7 @@ public sealed record GrnDto(
 /// <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, int BranchId, GrnStatus Status,
-    int CreatedBy, DateTime CreatedAt, DateTime? PostedAt, int LineCount,
+    int CreatedBy, DateTime CreatedAt, DateTime? PostedAt, int LineCount, decimal TotalValue,
     int? PurchaseInvoiceId, string? PurchaseInvoiceNo);
 
 public sealed record CreatedLayerDto(

Backend/ERPCore/Dtos/Items/ItemOverviewDtos.cs

@@ -0,0 +1,18 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Dtos.Items;
+
+/// <summary>
+/// Item row enriched with cross-module aggregates (current FIFO stock value, low-stock
+/// flag, last purchase, trailing-30-day sales) for the Items list page. Deliberately a
+/// separate endpoint from <see cref="ItemListItemDto"/>'s <c>GET /items</c> — that list
+/// also backs the GRN/PO/Requisition/RFQ item pickers, which don't need these aggregates
+/// computed on every keystroke.
+/// </summary>
+public sealed record ItemOverviewDto(
+    int ItemId, string Sku, string Name,
+    int CategoryId, int? SubCategoryId, int? BrandId,
+    EntityStatus Status,
+    decimal StockQty, decimal StockValue, bool IsLowStock,
+    DateTime? LastPurchaseDate, int? LastSupplierId, string? LastSupplierName,
+    decimal SalesQtyLast30Days);

Backend/ERPCore/Services/GrnService.cs

@@ -100,7 +100,7 @@ public sealed class GrnService : IGrnService
             .Skip(query.Skip).Take(query.PageSize)
             .Select(g => new GrnSummaryDto(
                 g.GrnId, g.DocNo, g.PoId, g.VendorId, g.WarehouseId, g.BranchId, g.Status,
-                g.CreatedBy, g.CreatedAt, g.PostedAt, g.Lines.Count,
+                g.CreatedBy, g.CreatedAt, g.PostedAt, g.Lines.Count, g.Lines.Sum(l => l.LineTotal),
                 g.PurchaseInvoiceId, g.PurchaseInvoice != null ? g.PurchaseInvoice.DocNo : null))
             .ToListAsync(ct);
 

Backend/ERPCore/Services/Interfaces/IItemService.cs

@@ -15,6 +15,12 @@ public interface IItemService
         PageQuery query, EntityStatus? status, int? categoryId, int? subCategoryId, int? brandId,
         TrackingMode? trackingMode, CancellationToken ct = default);
 
+    /// <summary>Same filters as <see cref="ListAsync"/>, enriched with stock value, low-stock,
+    /// last-purchase and trailing-30-day sales aggregates for the Items list page.</summary>
+    Task<PagedResponse<ItemOverviewDto>> GetOverviewAsync(
+        PageQuery query, EntityStatus? status, int? categoryId, int? subCategoryId, int? brandId,
+        CancellationToken ct = default);
+
     Task<ETagged<ItemDetailDto>?> GetAsync(int itemId, CancellationToken ct = default);
 
     Task<ETagged<ItemDetailDto>> CreateAsync(CreateItemRequest request, CancellationToken ct = default);

Backend/ERPCore/Services/ItemService.cs

@@ -1,4 +1,5 @@
 using ERPCore.Common.Http;
+using ERPCore.Domain;
 using ERPCore.Domain.Entities;
 using ERPCore.Domain.Enums;
 using ERPCore.Dtos.Config;
@@ -35,6 +36,7 @@ public sealed class ItemService : IItemService
     private readonly IRepository<Warehouse> _warehouses;
     private readonly IRepository<StockLayer> _stockLayers;
     private readonly IRepository<StockLedger> _stockLedger;
+    private readonly IRepository<GrnLine> _grnLines;
     private readonly IRepository<Batch> _batches;
     private readonly IRepository<Serial> _serials;
     private readonly IProductConfigService _config;
@@ -52,6 +54,7 @@ public sealed class ItemService : IItemService
         IRepository<Warehouse> warehouses,
         IRepository<StockLayer> stockLayers,
         IRepository<StockLedger> stockLedger,
+        IRepository<GrnLine> grnLines,
         IRepository<Batch> batches,
         IRepository<Serial> serials,
         IProductConfigService config,
@@ -68,6 +71,7 @@ public sealed class ItemService : IItemService
         _warehouses = warehouses;
         _stockLayers = stockLayers;
         _stockLedger = stockLedger;
+        _grnLines = grnLines;
         _batches = batches;
         _serials = serials;
         _config = config;
@@ -108,6 +112,82 @@ public sealed class ItemService : IItemService
         return PagedResponse<ItemListItemDto>.Create(rows, query.Page, query.PageSize, total);
     }
 
+    public async Task<PagedResponse<ItemOverviewDto>> GetOverviewAsync(
+        PageQuery query, EntityStatus? status, int? categoryId, int? subCategoryId, int? brandId,
+        CancellationToken ct = default)
+    {
+        var q = _items.Query().AsNoTracking();
+
+        if (!string.IsNullOrWhiteSpace(query.Q))
+        {
+            var term = query.Q.Trim();
+            q = q.Where(i => EF.Functions.ILike(i.Sku, $"%{term}%") || EF.Functions.ILike(i.Name, $"%{term}%"));
+        }
+        if (status is not null) q = q.Where(i => i.Status == status);
+        if (categoryId is not null) q = q.Where(i => i.CategoryId == categoryId);
+        if (subCategoryId is not null) q = q.Where(i => i.SubCategoryId == subCategoryId);
+        if (brandId is not null) q = q.Where(i => i.BrandId == brandId);
+
+        var total = await q.CountAsync(ct);
+        var page = await q.OrderBy(i => i.Sku)
+            .Skip(query.Skip).Take(query.PageSize)
+            .Select(i => new { i.ItemId, i.Sku, i.Name, i.CategoryId, i.SubCategoryId, i.BrandId, i.Status, i.ReorderSettings })
+            .ToListAsync(ct);
+        var itemIds = page.Select(i => i.ItemId).ToList();
+
+        // Current FIFO stock value/qty — every open layer, every warehouse.
+        var stockByItem = await _stockLayers.Query().AsNoTracking()
+            .Where(l => itemIds.Contains(l.ItemId) && l.QtyRemaining > 0)
+            .GroupBy(l => l.ItemId)
+            .Select(g => new { ItemId = g.Key, Qty = g.Sum(x => x.QtyRemaining), Value = g.Sum(x => x.QtyRemaining * x.UnitCost) })
+            .ToDictionaryAsync(x => x.ItemId, ct);
+
+        // On-hand per (item, warehouse), to compare against each item's reorder settings.
+        var onHandByItemWarehouse = (await _stockLayers.Query().AsNoTracking()
+            .Where(l => itemIds.Contains(l.ItemId) && l.QtyRemaining > 0)
+            .GroupBy(l => new { l.ItemId, l.WarehouseId })
+            .Select(g => new { g.Key.ItemId, g.Key.WarehouseId, Qty = g.Sum(x => x.QtyRemaining) })
+            .ToListAsync(ct))
+            .ToDictionary(x => (x.ItemId, x.WarehouseId), x => x.Qty);
+
+        // Last confirmed purchase (GRN) per item, with its vendor — pulled in bulk and
+        // reduced in memory rather than a "first per group" query EF can't always translate.
+        var grnCandidates = await _grnLines.Query().AsNoTracking()
+            .Where(l => itemIds.Contains(l.ItemId) && l.Grn!.PostedAt != null)
+            .Select(l => new { l.ItemId, PostedAt = l.Grn!.PostedAt!.Value, l.Grn.VendorId, VendorName = l.Grn.Vendor!.Name })
+            .ToListAsync(ct);
+        var lastPurchaseByItem = grnCandidates
+            .GroupBy(x => x.ItemId)
+            .ToDictionary(g => g.Key, g => g.OrderByDescending(x => x.PostedAt).First());
+
+        // Qty sold in the trailing 30 days, across every sale channel (invoice/slip/bundle),
+        // read off the stock ledger — the one place every sale channel posts uniformly.
+        var cutoff = DateTime.UtcNow.AddDays(-30);
+        var salesTypes = new[] { DocumentTypes.SalesInvoice, DocumentTypes.SalesSlip, DocumentTypes.BundleSale };
+        var salesByItem = await _stockLedger.Query().AsNoTracking()
+            .Where(l => itemIds.Contains(l.ItemId) && l.Direction == Direction.Out
+                && l.CreatedAt >= cutoff && salesTypes.Contains(l.SourceDocType))
+            .GroupBy(l => l.ItemId)
+            .Select(g => new { ItemId = g.Key, Qty = g.Sum(x => x.QtyBase) })
+            .ToDictionaryAsync(x => x.ItemId, x => x.Qty, ct);
+
+        var rows = page.Select(i =>
+        {
+            var stock = stockByItem.GetValueOrDefault(i.ItemId);
+            var isLowStock = i.ReorderSettings.Any(rs =>
+                onHandByItemWarehouse.GetValueOrDefault((rs.ItemId, rs.WarehouseId)) <= rs.ReorderPoint);
+            var lastPurchase = lastPurchaseByItem.GetValueOrDefault(i.ItemId);
+
+            return new ItemOverviewDto(
+                i.ItemId, i.Sku, i.Name, i.CategoryId, i.SubCategoryId, i.BrandId, i.Status,
+                stock?.Qty ?? 0m, stock?.Value ?? 0m, isLowStock,
+                lastPurchase?.PostedAt, lastPurchase?.VendorId, lastPurchase?.VendorName,
+                salesByItem.GetValueOrDefault(i.ItemId));
+        }).ToList();
+
+        return PagedResponse<ItemOverviewDto>.Create(rows, query.Page, query.PageSize, total);
+    }
+
     public async Task<ETagged<ItemDetailDto>?> GetAsync(int itemId, CancellationToken ct = default)
     {
         var item = await _items.Query().AsNoTracking()