Merge lane base check: develop 46c1d7310561

Merge lane base check: run the full gate on `develop` at `46c1d7310561ec6821447bbb04a25740d9b088cd` 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.

develop 46c1d7310561 red (develop_red reported): 11 API unit failures — easy-mode hosted-app pins/registry/queue + GET-mutates-state (fc725faca3, #7923) and missing _ENVELOPE after Slack/Gmail retirement (87c0936cf3, #7925). Memory: none applied.