Multi-stage Dockerfile:
- Stage 1: install deps, build TS, build web UI
- Stage 2: minimal production image with sqlite, only prod deps
- Exposes port 4738, uses /data volume for SQLite
docker-compose.yml for easy local deployment with .env support.
.dockerignore to keep the build context lean.
README updated with Docker usage.
.env.template adds DATA_DIR.
