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No dev server is running on port 8080 and no static files were found in /workspace.
How to fix
Dev server log /tmp/dev-server.log
INFO:     Started server process [29]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
INFO:     Uvicorn running on http://0.0.0.0:8080 (Press CTRL+C to quit)
INFO:     172.24.0.1:0 - "GET /robots.txt HTTP/1.1" 404 Not Found
INFO:     172.24.0.1:0 - "GET /sitemap.xml HTTP/1.1" 404 Not Found