Add production WSGI server and CLAUDE.md documentation

- Replace Flask development server with Waitress production WSGI server
- Add waitress>=2.1.0 dependency to pyproject.toml and Makefile
- Configure 4-thread server for better performance and stability
- Create comprehensive CLAUDE.md guide for future development
- Document architecture, deployment, testing, and common patterns
- Update README.md with production-ready feature and dependencies

Eliminates Flask development server warning and provides production-grade
web serving suitable for Raspberry Pi deployment.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Makefile

@@ -13,7 +13,7 @@ test:
 
 sync:
 	@echo "Installing/syncing dependencies..."
-	uv pip install flask numpy pyaudio RPi.GPIO
+	uv pip install flask numpy pyaudio RPi.GPIO waitress
 
 install: sync
 	@echo "Dependencies installed!"