- Added ID to turn label for easier updates
- Updated multiplayer.js to use turnLabel ID
- Reset turn label when switching modes or resetting game
- Improved UX by keeping player/turn info together
- Add polling mechanism to wait for window.game initialization
- Disable multiplayer button until game is fully initialized
- Enable button in DOMContentLoaded after game creation
- Prevents 'Game instance not found' error on production
This fixes the critical issue where clicking Multiplayer too quickly
would fail because window.game wasn't ready yet.
