- Add VITE_API_BASE_URL environment variable support to api.ts
- Update WebSocket hook to use env variable for separate backend deployment
- Add frontend/.env.example with configuration documentation
This enables:
- Local development: uses /api (relative path)
- Production deployment: set VITE_API_BASE_URL to backend URL
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
