Add complete REST API for lighting control

- Migrated from websockets to aiohttp for unified HTTP/WebSocket server
- Added REST endpoints: /api/pattern, /api/parameters, /api/state, /api/tempo/reset
- Implemented color palette API with 8-slot system and selected colors
- First selected color (index 0) is used as primary RGB for patterns
- All operations now available via simple HTTP requests (no WebSocket needed)
- Added comprehensive documentation: FRONTEND_API.md, COLOR_PALETTE_API.md
- Added test scripts: test_rest_api.sh, test_color_patterns.py
- Updated test/test_control_server.py for new /ws WebSocket path
- Configuration persistence via lighting_config.json
- Pattern parameters (n1-n4, brightness, delay) controllable via API
- WebSocket still available at /ws for legacy support

Pipfile

@@ -4,6 +4,7 @@ verify_ssl = true
 name = "pypi"
 
 [packages]
+aiohttp = "*"
 websockets = "*"
 spidev = "*"
 watchfiles = "*"