{"agent":"claude","input":"Set up GitHub Actions CI for this Gatsby site. Read package.json, package-lock.json, .prettierrc, .gitignore and gatsby-config.js first; note that the test script exits 1 on purpose and must not be a workflow step. Add a format:check script that runs prettier --check with the same glob as the format script. Write .github/workflows/ci.yml that runs on pull requests and pushes to the default branch with a concurrency group per ref, uses actions/setup-node with one pinned Node LTS version and npm caching, runs npm ci, npm run format:check and npm run build as separate steps, caches the .cache and public directories keyed on the lockfile and the Gatsby config and source files, and uploads public as an artifact. Run npm ci, npm run format:check and npm run build in the sandbox first; if the format check fails on existing files, format them in a separate commit. Push the branch, open a pull request that explains each step and why the test script is left out, and wait for the workflow to finish on the pull request, reporting its result.","resources":[{"url":"https://github.com/your-org/your-app"}]}