Merge lane base check: develop 35354ae08b12

Merge lane base check: run the full gate on `develop` at `35354ae08b123ea374109da2d0639f0ac8a89e73` 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 35354ae08b12 certified: full gate green (61318 passed, 0 failed); nothing ejected, queue empty. Memory: none applied.