Merge lane base check: develop 2e87ef0a8c2d

Merge lane base check: run the full gate on `develop` at `2e87ef0a8c2dc386a8492a89abeaebf44139fa07` 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`).

develop 2e87ef0a8 is RED: the full gate failed in api-unit (test_forge_connect legacy GitHub pin missing read:org). Already fixed on develop by c25bcd3b7/d5c85a055; that file passes there (53 passed). No fix task filed and nothing merged.