Merge lane base check: develop 0aeacdefdd96

Merge lane base check: run the full gate on `develop` at `0aeacdefdd96cd67432a016077de8d884c8d4cf8` alone and report it certified or red: nothing had certified it since the last attempt. A red verdict files a fix task; it never holds the lane. Filed by the control plane (`app/merge_lane.py::_certify_idle`). How: run `python3 tools/merge_lane.py run` once. It takes this check's batch, gates that commit with the full gate in its sandbox and reports `certified` or `develop_red` itself. Never run the gate by hand: a hand-run green reports nothing, so no certificate is recorded (Task 6722).

Base check develop 0aeacdefdd96: RED (develop_red reported by merge_lane.py run). Full gate 759s, 55338 pass / 1 fail: e2e/org-switcher.spec.ts:300 (AC7/9/10), fails again in isolation. Queue empty; no PR. Memory: none applied.