Refactor sales pipeline: ShopPO, Invoice, SysConfig models

Major refactor replacing Sale/Order with ShopPO → Invoice → LoadingSheet flow. Removed legacy Sale/Order models and features; introduced ShopPO, ShopPOItem, Invoice, LoadingSheetOrder, and SysConfig models. Updated related entities, enums, repositories, and controllers. Added new migrations for schema changes and system config. Overhauled business logic and DI registrations. Updated documentation with migration plan.

Distribution/Features/DeliveryRide/DeliveryTaskRepository.cs

@@ -1,4 +1,4 @@
-using Distribution.Data;
+using Distribution.Data;
 using Distribution.Models;
 using Microsoft.EntityFrameworkCore;
 
@@ -8,27 +8,27 @@ public class DeliveryTaskRepository(AppDBContext context) : IDeliveryTaskReposit
 {
     public async Task<DeliveryTask?> GetByIdAsync(Guid id) =>
         await context.DeliveryTasks
-            .Include(t => t.Order)
+            .Include(t => t.ShopPO)
                 .ThenInclude(o => o.Store)
-            .Include(t => t.Order)
-                .ThenInclude(o => o.OrderItems)
+            .Include(t => t.ShopPO)
+                .ThenInclude(o => o.Items.Where(i => i.IsActive))
                     .ThenInclude(i => i.Item)
             .FirstOrDefaultAsync(t => t.Id == id);
 
     public async Task<List<DeliveryTask>> GetByRideIdAsync(Guid rideId) =>
         await context.DeliveryTasks
-            .Include(t => t.Order)
+            .Include(t => t.ShopPO)
                 .ThenInclude(o => o.Store)
-            .Include(t => t.Order)
-                .ThenInclude(o => o.OrderItems)
+            .Include(t => t.ShopPO)
+                .ThenInclude(o => o.Items.Where(i => i.IsActive))
                     .ThenInclude(i => i.Item)
             .Where(t => t.FK_RideId == rideId)
             .OrderBy(t => t.Sequence)
             .ToListAsync();
 
-    public async Task<bool> ExistsForOrderAndRideAsync(Guid orderId, Guid rideId) =>
+    public async Task<bool> ExistsForOrderAndRideAsync(Guid shopPOId, Guid rideId) =>
         await context.DeliveryTasks
-            .AnyAsync(t => t.FK_OrderId == orderId && t.FK_RideId == rideId);
+            .AnyAsync(t => t.FK_ShopPOId == shopPOId && t.FK_RideId == rideId);
 
     public async Task AddAsync(DeliveryTask task) =>
         await context.DeliveryTasks.AddAsync(task);