ci: align deployment on Kuby (Docker + rsync + SSH key + healthcheck + rollback)

- Add HTTP /health endpoint (aiohttp) for Docker healthcheck + post-deploy check
- Dockerfile HEALTHCHECK hits /health; docker-compose exposes 1890, container vision-bot
- scripts/deploy_runner.sh runs on .117 (docker compose build/restart)
- .forgejo/workflows/deploy.yml: single job on omhk-deploy runner (clone, syntax test,
  rsync, deploy, health check, auto-rollback) like Kuby
- .forgejo/workflows/ci.yml: single job (ruff + pytest) on dev/PR

Dockerfile

@@ -18,6 +18,6 @@ RUN pip install --no-cache-dir -r requirements.txt
 COPY . .
 
 HEALTHCHECK --interval=30s --timeout=10s --start-period=30s --retries=3 \
-    CMD python -c "import discord; print('ok')" || exit 1
+    CMD curl -fsS http://localhost:1890/health || exit 1
 
 CMD ["python", "vision.py"]