Function reap_branch_and_reviews 

fn reap_branch_and_reviews(
    workspace: &Arc<Workspace>,
    repo: Option<&Path>,
    review_key: Option<&(String, String)>,
    label: &str,
) -> Option<String>

Reap the worker’s branch and, once that is gone, the review state keyed to it. Returns the warning a kept branch produces, which the caller’s result carries.

The branch outlives the worktree - git worktree remove does not delete one - so this runs after a removal, and also for a worktree that was already gone: gone means the branch is no longer checked out, which is exactly when the delete is safe.