feat(scripting): add script add-component api

managed/XCEngine.ScriptCore/Component.cs

@@ -34,6 +34,11 @@ namespace XCEngine
             return GameObject.GetComponent<T>();
         }
 
+        public T AddComponent<T>() where T : Component
+        {
+            return GameObject.AddComponent<T>();
+        }
+
         public bool TryGetComponent<T>(out T component) where T : Component
         {
             component = GetComponent<T>();