CI / shellcheck + selftests (pull_request) Successful in 1m27s
`daniel/zemyna` enabled `default_delete_branch_after_merge` after this branch was written, so the deleted-branch signal will fire there on future merges. That makes the setting worth recommending — it is the cheapest case for this scheme, decidable from `ls-remote` with no checkout, no objects and no walk — and it does not make the ancestry signal redundant. Three things it leaves behind, now enumerated in the README's eviction section rather than implied: every branch merged before the setting was turned on, of which zemyna carried 48 and which nothing retroactively deletes; every merge whose deletion the forge declines or is never asked to make, since it is best-effort and silent and an API merge without the flag never asks; and every repo that has not enabled it, which is the default. Two present-tense claims about one repo's configuration are reworded into the conditions they were standing in for, in prune-cache.sh's header and beside is_merged_dead, plus the two in the selftest that asserted the forge keeps branches rather than describing the fixture. No behaviour change; the suite is green and unchanged at 61 assertions. Refs #20. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01JXMQCJ5Eg5f9G9cfYzyh4Z