fix: update HEALTHCHECK command to use curl for improved reliability

Author: maesse

Dockerfile

@@ -27,8 +27,8 @@ ENV FRONTEND_DIST_DIR=/app/frontend-dist \
     INTERCEPTER_MAX_REQUESTS=100 \
     INTERCEPTER_RETENTION_SECONDS=86400
 EXPOSE 8181
+
 HEALTHCHECK --interval=10s --timeout=3s --start-period=10s --retries=3 \
-    CMD python -c "import sys,urllib.request; \
-u=urllib.request.urlopen('http://127.0.0.1:8181/healthz'); \
-sys.exit(0 if u.getcode()==200 else 1)" || exit 1
+    CMD curl -fsS http://127.0.0.1:8181/healthz || exit 1
+
 CMD ["python", "-m", "uvicorn", "backend.app.main:app", "--host", "0.0.0.0", "--port", "8181"]