update-pr

Context

User is working on a PR and has changes to commit (by "changes" we mean both staged and unstaged).

The whole skill turns on one question: has anyone anchored expectations to my current commit layout?

• rewritable — nobody has. There's no PR, or the PR was only touched by the user (or by CI/agents acting on the user's behalf). Commits are a private draft — you may rewrite history freely.
• append-only — somebody has. There's a PR and someone else already reviewed or commented on it in a meaningful way. Commits are a shared contract — never rewrite what they've already seen.

Establishing the state