Fix GRN pricing

Distribution/Features/Grn/GrnDTOs.cs

@@ -13,20 +13,32 @@ public record GrnItemRequest(
     // Populated only when the item has TracksSerialNumbers set — must contain exactly AcceptedQuantity entries.
     List<string>? SerialNumbers = null,
     // Set for a direct receipt line (no purchase order).
-    Guid? ItemId = null);
+    Guid? ItemId = null,
+    // Cost per base-UOM unit. Null on a PO line falls back to the PO line's unit cost; null on a direct line is 0.
+    decimal? UnitCost = null,
+    // Null falls back to the GRN-wide percentage.
+    decimal? DiscountPercent = null,
+    decimal? VatPercent = null,
+    // Free-issue units: stocked but not costed. Serial/batch entries must cover accepted + free.
+    int FreeQuantity = 0);
 
 public record CreateGrnRequest(
     Guid WarehouseId,
     List<GrnItemRequest> Items,
     // TEMPORARY: required while auth doesn't resolve a logged-in user server-side — see testbug.md #28.
-    Guid? ReceivedByUserId = null);
+    Guid? ReceivedByUserId = null,
+    // GRN-wide defaults for lines that don't set their own.
+    decimal? DiscountPercent = null,
+    decimal? VatPercent = null);
 
 public record CreateFlatGrnRequest(
     Guid PurchaseOrderId,
     Guid WarehouseId,
     List<GrnItemRequest> Items,
     // TEMPORARY: required while auth doesn't resolve a logged-in user server-side — see testbug.md #28.
-    Guid? ReceivedByUserId = null);
+    Guid? ReceivedByUserId = null,
+    decimal? DiscountPercent = null,
+    decimal? VatPercent = null);
 
 /// <summary>A goods receipt with no purchase order. SupplierId is optional.</summary>
 public record CreateDirectGrnRequest(
@@ -34,7 +46,9 @@ public record CreateDirectGrnRequest(
     List<GrnItemRequest> Items,
     Guid? SupplierId = null,
     // TEMPORARY: required while auth doesn't resolve a logged-in user server-side — see testbug.md #28.
-    Guid? ReceivedByUserId = null);
+    Guid? ReceivedByUserId = null,
+    decimal? DiscountPercent = null,
+    decimal? VatPercent = null);
 
 public record GrnBatchLineResponse(string? BatchNumber, DateTime? ExpiryDate, int Quantity);
 
@@ -47,7 +61,17 @@ public record GrnItemResponse(
     int AcceptedQuantity,
     int RejectedQuantity,
     List<GrnBatchLineResponse> Batches,
-    List<string> SerialNumbers);
+    List<string> SerialNumbers,
+    decimal UnitCost,
+    decimal DiscountPercent,
+    decimal VatPercent,
+    // Accepted qty x unit cost, before discount.
+    decimal GrossAmount,
+    decimal DiscountAmount,
+    decimal VatAmount,
+    // Gross - discount + VAT.
+    decimal LineTotal,
+    int FreeQuantity);
 
 public record GrnResponse(
     Guid Id,
@@ -59,4 +83,13 @@ public record GrnResponse(
     string? SupplierName,
     DateTime ReceivedAt,
     DateTime CreatedAt,
-    List<GrnItemResponse> Items);
+    List<GrnItemResponse> Items,
+    decimal DiscountPercent,
+    decimal VatPercent,
+    // Sum of line gross amounts.
+    decimal SubTotal,
+    decimal DiscountAmount,
+    // SubTotal - DiscountAmount (the base VAT is charged on).
+    decimal TaxableAmount,
+    decimal VatAmount,
+    decimal TotalAmount);