- Remove separate backend/ and frontend/ Dockerfiles
- Add root Dockerfile (3-stage: frontend build → backend build → runtime)
- Frontend static files served by Express from /public
- Simplify docker-compose to 3 services: mongodb, redis, app (port 3579)
- Fix vite proxy not to strip /api prefix from paths
- Default API URL to relative /api instead of hardcoded localhost
Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>