unsafe drag drop test

- unsafe because of entity reference
- unsafe because of unsafe code lol
- fixes in parent/child system

Nerfed.Runtime/Util/Transform.cs

@@ -28,10 +28,7 @@ namespace Nerfed.Runtime.Util
         // Relation goes from child to parent.
         public static void SetParent(in World world, in Entity child, in Entity parent)
         {
-            if (world.Related<ChildParentRelation>(parent, child))
-            {
-                RemoveParent(world, parent);
-            }
+            RemoveParent(world, child);
 
             world.Relate(child, parent, new ChildParentRelation());
             world.Set(child, new Child());
@@ -47,8 +44,10 @@ namespace Nerfed.Runtime.Util
                 return;
             }
 
+            Entity parent = world.OutRelationSingleton<ChildParentRelation>(child);
+
             // TODO: Check if Unrelate all also unrelates incomming relations..?
-            world.UnrelateAll<ChildParentRelation>(child);
+            world.Unrelate<ChildParentRelation>(child, parent);
             world.Remove<Child>(child);
             world.Set(child, new Root());
         }