Agent Skills: review-prep

Prepare a human reviewer to review someone else's pull request — machine-check verbalizable perspectives with subagents, then hand over a self-contained HTML briefing separating what is safe to skim from what needs the human's design judgment. Strictly read-only against GitHub. Use when the user will themselves review someone else's PR — assigned as reviewer, asking where to start reading before passing judgment, or merely stating they have to review a PR (a bare URL or number with no explicit ask). Not for fully automated review that ends with AI findings, and not for responding to feedback on the user's own PR.