H617A RC3 — preserve newer Live edits

Includes RC2's response-driven segment verification and v7.6.2/#249 GATT fixes.

Installed browser testing found that enabling Live and immediately editing could allow an older saved Apply to cancel the newer preview while initial persistence was running. RC3 admits Apply before that save yields. Cancellation before ownership now records failure without a second admission that could invalidate newer previews. Possible-write restoration retains the existing ownership and guards; no settling sleeps or new locks.

Software gate: 2,810 Python tests passed (79 skipped), 269 frontend unit tests, 33 browser tests, and protocol/type/lint/generated-output checks. Independent correctness and fresh Ponytail reviews closed both ordering findings, including cancellation and storage-failure probes.

RC2 passed installed static/segment checks, all eleven music and seven native-DIY API workflows, representative installed UI controls, normal idle reconnect and a short off-state polling window. Cleanup restored the authorised off/5% warm baseline and removed temporary items. RC3 must qualify the immediate-edit race and repeat affected workflows.

Rendering and onboard-microphone response await owner observation. ACK and selector readback do not establish resident-payload equality. Induced failed-application restoration remains software-qualified; restart persistence and longer normal-use qualification remain outstanding. New protocol coverage stays speculative, and unknown physical IC count gates dependent controls. Exact-device scope: H617A HW 3.01.01 / FW 3.02.24.

Install exact tag v7.7.0-rc.3.h617a through HACS; runtime manifest 7.7.0rc3. Every HA restart requires fresh owner approval. Stable publication remains gated on qualification.