Add supply contract entity

Hcs.WebApp/Data/Hcs/SupplyContract.cs

@@ -0,0 +1,17 @@
+namespace Hcs.WebApp.Data.Hcs
+{
+    public class SupplyContract
+    {
+        public int Id { get; set; }
+
+        public Guid? HcsId { get; set; }
+
+        public string? ThirdPartyId { get; set; }
+
+        public DateTime? SyncedAt { get; set; }
+
+        public int? LastSyncOperationId { get; set; }
+
+        public virtual Operation? LastSyncOperation { get; set; }
+    }
+}