Branch: Rename If Needed

Assess and Rename Current Branch

1. Gather the facts in one call: "$HOME"/.claude/library/scripts/branch-facts.sh; it emits JSON including the current branch name, its convention compliance, and the commit/diff shape. Judge from that; only run git log main..HEAD --oneline / git diff main..HEAD --name-only when the facts alone can't tell you what the branch is about.
2. $desired-name given: treat it as the target: check it against convention (Step 3's format rules), flag any mismatch, then proceed to Step 5 with it.
3. No argument: derive the right name yourself from what the branch actually contains:
   • Format: <prefix>/<short-description>, all lowercase, hyphens, imperative mood (add-feature, never adds-feature or adding-feature)
   • Prefix from the canonical set: feat, fix, enhance, refactor, test, docs, config, chore, ci, deps, hotfix, spike, agents, chosen from the dominant nature of the commits, not the first commit
   • Description from the work's effect, not its file list
4. If the current name already satisfies convention and accurately describes the work, say so and stop; no rename for renaming's sake.
5. Otherwise present the suggested (or user-supplied) name against the current one, with one line of reasoning, and await approval. On approval:
   • Rename locally: git branch -m <new-name>
   • If the old branch was pushed: first run gh pr list --head <old-name> and gh pr list --base <old-name>. An open PR on either means stop and rename nothing: deleting a head branch closes its PR permanently (GitHub does not follow renames), and deleting a branch that is the base of an open PR orphans a stacked child. Report that; a branch inside a stack is renamed safely only via gh stack modify (its rename operation retargets the stack for you), otherwise the rename waits until the PRs merge or close. With no open PR either way: git push origin HEAD:<new-name>, then git push origin --delete <old-name>, then git branch --set-upstream-to=origin/<new-name>
   • Never touch the remote when the branch was never pushed; the facts output shows whether an upstream exists.