fix: Issues With Behaviours Entering / Leaving the Hierarchy Callbacks Not Firing

Engine.Core/GameManager.cs

@@ -140,12 +140,12 @@ public class GameManager : BaseEntity, IGameManager
         gameObject.OnFinalized += OnGameObjectFinalize;
         gameObject.OnExitedHierarchy += OnGameObjectExitedHierarchy;
 
-        foreach (ITransform child in gameObject.Transform.Children)
-            Register(child.GameObject);
-
         if (!gameObject.Initialize())
             throw new Exception($"{nameof(gameObject)} can't be initialized");
 
+        foreach (ITransform child in gameObject.Transform.Children)
+            Register(child.GameObject);
+
         _gameObjects.Add(gameObject);
         _hierarchyObjects.Add(gameObject);