feat: Git-based incremental server deployment with direct folder copy

- Removed tar archive approach - no longer needed
- Server now uses persistent git repository (~/.festival-archive-repo)
- Deployment via git pull for incremental updates (fast, delta compression)
- Fallback to direct festival-XX folder copying when Node.js unavailable
- Removed chown command (requires sudo) - only chmod for permissions
- Updated CLI commands: both 'deploy' and 'server' work now
- Enhanced .env.example with password auth documentation
- CLI now shows Git deployment progress in interactive mode
- All changes tested successfully with password authentication