Compose settings:
- Reworked docker-compose.yml to use environment-variable driven configuration.
- Added shared app env anchors for backend and worker to reduce duplication.
- Made ports, credentials, security limits, SMTP, and storage options configurable.
Production profile:
- Added docker-compose.prod.yml override to close internal service ports.
- Keeps external attack surface minimal for Linux server deployments.
Docs and ops:
- Added .env.docker.example with full variable set for server setup.
- Updated README with quick-start and production launch commands.
