Main's 0aa569e72 makes a key whole or not at all, as this branch's 3867b6ece did, in
another form: main's keys.rs is kept, and the workflow names its test,
keys::tests::keys_made_at_once_are_one_key, in place of this branch's.
Co-Authored-By: Claude Opus 5.5 <[email protected]>