refactor: renamed flipper_controller.dart to controlled_flipper.dart (#128)

* refactor: renamed files

* refactor: renamed barrel file export

lib/game/components/components.dart

@@ -2,7 +2,7 @@ export 'board.dart';
 export 'bonus_word.dart';
 export 'chrome_dino.dart';
 export 'controlled_ball.dart';
-export 'flipper_controller.dart';
+export 'controlled_flipper.dart';
 export 'flutter_forest.dart';
 export 'jetpack_ramp.dart';
 export 'kicker.dart';