Merge lane base check: develop 3d7963e322ae

Merge lane base check: run the full gate on `develop` at `3d7963e322ae4534231e72c6c10166189e3c96c7` 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 3d7963e322ae reported develop_red: one vitest test failed in both full-gate runs (Nodes.test.tsx "R13b re-issue token", expected false to be true), likely from Task 10754's node-token change. No PR ejected. Memory: none applied.