chore(tests): prune obsolete probes and define truthful offline test gates

scripts/rea/probe-custom-connectors-20261016.json

@@ -1 +0,0 @@
-{"actions":[{"kind":"click","step_id":"close-qq-mail-detail","selector":".connector-detail-close","frames":0},{"kind":"click","step_id":"open-custom-connectors","selector":".connector-topbar-action-btn","frames":0},{"kind":"wait","step_id":"custom-connectors-ready","duration_ms":500,"frames":1}]}