fix(regular-store): deduct inventory and restore on cancel

- UserOrderService.SubmitShopBuyOrder: inject IInventoryService; validate
  available stock per item before any financial operation; call ConfirmSaleAsync
  and increment Product.SaleCount after order is persisted.
- CancelOrderByAdminCommandHandler: inject IInventoryService; include
  FactorDetails in query; call ProcessReturnAsync for each item so stock
  is restored when an order is cancelled by admin.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/CMSMicroservice.Application/OrderManagementCQ/Commands/CancelOrderByAdmin/CancelOrderByAdminCommandHandler.cs

@@ -10,15 +10,18 @@ public class CancelOrderByAdminCommandHandler : IRequestHandler<CancelOrderByAdm
 {
     private readonly IApplicationDbContext _context;
     private readonly ICurrentUserService _currentUser;
+    private readonly IInventoryService _inventoryService;
     private readonly ILogger<CancelOrderByAdminCommandHandler> _logger;
 
     public CancelOrderByAdminCommandHandler(
         IApplicationDbContext context,
         ICurrentUserService currentUser,
+        IInventoryService inventoryService,
         ILogger<CancelOrderByAdminCommandHandler> logger)
     {
         _context = context;
         _currentUser = currentUser;
+        _inventoryService = inventoryService;
         _logger = logger;
     }
 
@@ -33,6 +36,7 @@ public class CancelOrderByAdminCommandHandler : IRequestHandler<CancelOrderByAdm
         var order = await _context.UserOrders
             .Include(x => x.User)
             .ThenInclude(x => x.UserWallets)
+            .Include(x => x.FactorDetails)
             .FirstOrDefaultAsync(x => x.Id == request.OrderId && !x.IsDeleted, cancellationToken);
 
         if (order == null)
@@ -87,6 +91,26 @@ public class CancelOrderByAdminCommandHandler : IRequestHandler<CancelOrderByAdm
 
         await _context.SaveChangesAsync(cancellationToken);
 
+        // Restore inventory for each item (only if order was not yet delivered)
+        if (order.FactorDetails != null && order.FactorDetails.Any())
+        {
+            foreach (var item in order.FactorDetails)
+            {
+                var restored = await _inventoryService.ProcessReturnAsync(
+                    item.ProductId, ProductType.RegularProduct,
+                    item.Count, order.Id,
+                    note: $"برگشت موجودی — لغو سفارش #{order.Id} توسط Admin",
+                    cancellationToken: cancellationToken);
+
+                if (!restored)
+                {
+                    _logger.LogWarning(
+                        "Failed to restore inventory for ProductId={ProductId} on cancel OrderId={OrderId}",
+                        item.ProductId, order.Id);
+                }
+            }
+        }
+
         _logger.LogInformation(
             "Order cancelled by admin. OrderId: {OrderId}, Reason: {Reason}, Refunded: {Refunded}, Admin: {AdminId}",
             order.Id,