refactor: improved casting

lib/game/components/flutter_forest.dart

@@ -96,9 +96,9 @@ class _DashNestBumperBallContactCallback
     extends ContactCallback<DashNestBumper, Ball> {
   @override
   void begin(DashNestBumper dashNestBumper, _, __) {
-    if (dashNestBumper.parent is FlutterForest) return;
+    final parent = dashNestBumper.parent;
-
+    if (parent is FlutterForest) {
-    final parent = dashNestBumper.parent! as FlutterForest;
       parent.controller.activateBumper(dashNestBumper);
     }
+  }
 }