fix: Adds DupeExcludedProperty to Items (#1556)

Projects/Server/Items/Item.cs

@@ -3348,6 +3348,16 @@ public class Item : IHued, IComparable<Item>, ISpawnable, IObjectPropertyListEnt
         }
     }
 
+    private static readonly HashSet<string> _excludedProperties = new()
+    {
+        "Parent",
+        "Next",
+        "Previous",
+        "OnLinkList"
+    };
+
+    public virtual bool DupeExcludedProperty(string propertyName) => _excludedProperties.Contains(propertyName);
+
     public virtual void OnAfterDuped(Item newItem)
     {
     }