fn reap_worker_branch(repo: &Path, label: &str) -> Option<String>Expand description
Reap the worktree-<label> branch claude creates for a worker’s
worktree, which outlives the worktree itself. Returns a warning when
the branch was left in place, None when it was deleted or never
existed.
The branch is named by convention, never taken from whatever the worktree had checked out: a worker that made its own feature branch has real work on that one, and this must not aim at it.