A live QR scan reached the app but rejected: 'reader not on an access-equipped
lane' — the dispatcher requires an access device on the reader's lane. Add a
no-op stub-access driver (access category, no config) whose pulseOpen only logs
and does no device I/O, so the QR->permit->accept flow (incl. the beep) can be
tested without the Dingtian relay connected. Not for production; registered in
the catalog.
