- Implement `ScrabbleGame` scene with drag-and-drop, rack management, and animated tile placement.
- Add pure JS modules for Scrabble rules, scoring, and tile data (`ScrabbleLogic`, `ScrabbleTiles`).
- Create server-side dictionary trie and DFS-based move generator for AI (`scrabbleEngine`).
- Register game routes for move validation and AI move requests (`wordRoutes`).
- Update game registry, opponent selection, and preload scenes to support Scrabble.
- Include custom font (`YummyCupcakes`) for the scorepad UI.
