Inventor draft of the fourth approval action alongside approve / reject /
revoke. Open questions in §2 will be resolved via AskUserQuestion before
any coder work. Recommendations folded in inline.
Verified live state before designing: status enum already carries an
unused 'superseded' value; entity approval_status is approved/pending/legacy
only; decision_note exists as free text; the existing decide() kernel
handles approve / reject / revoke with a single switch.