simplify-and-harden-ci

MEDIUM W011: Third-party content exposure detected (indirect prompt injection risk).

• Third-party content exposure detected (high risk: 0.85). The skill’s runtime workflow ingests the PR’s changed code/files (outsider-authored content from other contributors) into the LLM context via the “review only files changed in this PR” CI prompt path.

MEDIUM W012: Unverifiable external dependency detected (runtime URL that controls agent).

• Potentially malicious external URL detected (high risk: 0.80). The skill requires and invokes the external GitHub extension/action "github/gh-aw" (installed via "gh extension install github/gh-aw" and used as "uses: github/gh-aw/actions/setup-cli@main"), which is fetched and executed at CI runtime and thus represents an external runtime dependency that executes remote code.