Fork-based PRs (like PR #498) caused all CI checks to fail due to: - ci-quality-gate: checkout failed because fork branch names don't exist in the base repo. Now uses commit SHA for PR events. - skill-security-audit: comment posting failed with read-only GITHUB_TOKEN. Now continues on error and writes results to job summary as fallback. - claude-code-review: fallback comment step failed silently. Now continues on error and writes status to job summary. https://claude.ai/code/session_01X1RKFAkEwxgg6gQvJG1KCa