Make container more robust (#95)

Reviewed-on: #95

12 files changed (+149, -66)
Key changes:
1. Monolithic container — Replaced the two-service compose setup (backend + frontend/caddy) with a single timetracker container. Caddy is now built into the image rather than running as a separate container.
2. Supervisord process manager — Added supervisor.conf and installed supervisor in the Dockerfile. entrypoint.sh now delegates to supervisord to manage three processes: Caddy, Gunicorn, and Qcluster — replacing manual trap/signaling logic.
3. Bundled Caddy — The Dockerfile now downloads and installs Caddy v2.9.1 directly into the image (/usr/local/bin/caddy). The Caddyfile was updated to use reverse_proxy localhost:8001 and serves static files from /home/timetracker/app/static.
4. Configurable deployment — Added .env.example with configurable environment variables: TZ, PUID/PGID, TIMETRACKER_EXTERNAL_PORT, DATA_DIR, CSRF_TRUSTED_ORIGINS. docker-compose.yml now references these with sensible defaults.
5. UID/GID flexibility — entrypoint.sh uses usermod/groupmod at startup to remap the timetracker user to the host-specified PUID/PGID, avoiding permission issues with mounted volumes.
6. Database & static files — settings.py now respects DATA_DIR env var for the SQLite database path. STATIC_ROOT changed to BASE_DIR / "static".
7. Dev improvements — New Caddyfile.dev (with browse enabled for static files) and updated Makefile dev-prod target runs Caddy alongside Django in development.
8. Tests — Re-enabled the test step in the Docker build GitHub Actions workflow.

.github/workflows/build-docker.yml

@@ -22,8 +22,8 @@ jobs:
       - name: Run Migrations
         run: uv run python manage.py migrate
 
-      # - name: Run Tests
-      #   run: PROD=1 uv run pytest
+      - name: Run Tests
+        run: uv run --with pytest-django pytest
 
   build-and-push:
     needs: test