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>

pyproject.toml

@@ -9,6 +9,7 @@ dependencies = [
     "numpy>=1.21.0",
     "pyaudio>=0.2.13",
     "RPi.GPIO>=0.7.1",
+    "waitress>=2.1.0",
 ]
 
 [project.scripts]