Reviews GitHub Actions workflow YAML for supply-chain and injection risks: pull_request_target with PR checkout, untrusted github.event text in run steps, actions pinned to tags or branches instead of commit SHAs, missing or write-all permissions, secrets in shell commands, curl | bash, self-hosted runners on PRs, and missing timeouts. Use before merging CI changes or auditing a repo. Includes a stdlib Python linter with --self-test.
