* feat: prep reviewer repo at init and load repo skills
Clone + checkout the PR head during reviewer agent init so SkillsMiddleware
can discover the repo's .agents/skills and .claude/skills from disk at its
one-shot scan, and so the LLM no longer narrates the clone mid-run.
Co-authored-by: open-swe[bot] <open-swe@users.noreply.github.com>
* fix: load reviewer skills from trusted base sha and fetch PR pull ref
Address review findings: skills are now extracted from the PR base sha via
git archive into a dir outside the checkout (prevents PR-authored SKILL.md
prompt injection), and repo prep fetches refs/pull/<n>/head with a strict
checkout so fork PRs fail loudly instead of silently reviewing the default
branch.
* fix: drop ref from skill-extraction log to satisfy CodeQL
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Co-authored-by: open-swe[bot] <open-swe@users.noreply.github.com>
