Add initial hcs database schema creation

Hcs.WebApp/Data/Hcs/Registry.cs

@@ -0,0 +1,11 @@
+namespace Hcs.WebApp.Data.Hcs
+{
+    public class Registry
+    {
+        public string Id { get; set; }
+
+        public int Number { get; set; }
+
+        public virtual ICollection<RegistryElement> Elements { get; set; } = [];
+    }
+}