Replaces the v1.1.1 HANDBACK (its release record is preserved on
main via the v1.1.1 commit log). v1.1.2 HANDBACK covers the seven
sections the implementation brief requires plus a tests-added
breakdown and open-question list for the reviewer.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>