Update methods to be internal, remove invocation bloat

Assets/Scripts/Core/ItemManager.cs

@@ -50,18 +50,18 @@ namespace Core
 
         public override int ManagedAwakePriority => 75; // Item registry
         
-        protected override void OnManagedAwake()
+        internal override void OnManagedAwake()
         {
             // Set instance immediately (early initialization)
             _instance = this;
         }
         
-        protected override void OnManagedStart()
+        internal override void OnManagedStart()
         {
             Logging.Debug("[ItemManager] Initialized");
         }
         
-        protected override void OnSceneReady()
+        internal override void OnSceneReady()
         {
             // Replaces SceneLoadStarted subscription for clearing registrations
             ClearAllRegistrations();