Dependency edges can now require the prerequisite be ACTIVE at FMCSA, not
just our handler completed. mc-authority/ucr/d&a now wait for an active
USDOT; BOC-3 stays parallel-OK (can file while authority pending). Adds
_prerequisite_active() polling FMCSA QC API, a waiting_on_activation hold
state with next-check timestamp, and a 21-day authority vetting estimate
for customer comms. Branch logic unit-tested.