Fix GRN pricing

Distribution/Models/GoodsReceipt.cs

@@ -1,4 +1,5 @@
 using System.ComponentModel.DataAnnotations.Schema;
+using Microsoft.EntityFrameworkCore;
 
 namespace Distribution.Models
 {
@@ -27,6 +28,14 @@ namespace Distribution.Models
 
         public DateTime ReceivedAt { get; set; } = DateTime.Now;
 
+        /// <summary>GRN-wide default discount %, applied to any line that doesn't set its own.</summary>
+        [Precision(5, 2)]
+        public decimal DiscountPercent { get; set; }
+
+        /// <summary>GRN-wide default VAT %, applied to any line that doesn't set its own.</summary>
+        [Precision(5, 2)]
+        public decimal VatPercent { get; set; }
+
         public ICollection<GoodsReceiptItem> Items { get; set; } = [];
     }
 }

Distribution/Models/GoodsReceiptItem.cs

@@ -1,4 +1,5 @@
 using System.ComponentModel.DataAnnotations.Schema;
+using Microsoft.EntityFrameworkCore;
 
 namespace Distribution.Models
 {
@@ -24,6 +25,22 @@ namespace Distribution.Models
         /// <summary>Damaged/short at receipt, not added to stock.</summary>
         public int RejectedQuantity { get; set; } = 0;
 
+        /// <summary>
+        /// Units the supplier gave at no charge. Received into stock like accepted units, but never
+        /// costed and never counted against the purchase order's ordered quantity.
+        /// </summary>
+        public int FreeQuantity { get; set; } = 0;
+
+        /// <summary>Cost per base-UOM unit. Only accepted units are costed.</summary>
+        [Precision(18, 2)]
+        public decimal UnitCost { get; set; }
+
+        [Precision(5, 2)]
+        public decimal DiscountPercent { get; set; }
+
+        [Precision(5, 2)]
+        public decimal VatPercent { get; set; }
+
         /// <summary>Populated when the received item tracks batches and/or expiry dates.</summary>
         public ICollection<GoodsReceiptItemBatch> Batches { get; set; } = [];