{"agent":"codex","input":"Upgrade this FastAPI app's Python dependencies with uv lock --upgrade while preserving existing compatibility constraints. Inspect backend/pyproject.toml, the root uv.lock, existing test scripts and database configuration. Start a disposable PostgreSQL database in the sandbox, install the baseline and run uv run pytest from backend with the required test environment. Update and sync the dependencies, then run the tests again against PostgreSQL. Leave out dependency groups that introduce failures and explain why. Do not touch production data, weaken tests or upgrade the frontend. Open a pull request with one line per retained package bump, exact check output and deferred upgrades.","resources":[{"url":"https://github.com/your-org/your-app"}]}