Restore samples.json loading for AI drawing

Clean up untracked files, gitignore samples.js and xss-test.html

Fix health check: use PORT 7860 to match HF Spaces default, add /health endpoint

Remove unused QuickDraw samples.json (1MB)

Remove test file and unused samples.js

Remove AI player and QuickDraw recognition

Initial commit: Skrawl multiplayer drawing game with QuickDraw AI recognition