refactor: split code into services and files

Author: user-of-github

games/running-ball-babylonjs/src/game/game-services/ui-manager.service..ts renamed to games/running-ball-babylonjs/src/game/game-services/ui-elements.service..ts

@@ -1,4 +1,4 @@
-import { Game } from './game/Game';
+import { Game } from './game/game';
 import type { GameHTMLElementsRefs } from './game/types';
 
 const main = () => {