VSN-2941/ feat(planning): allow driver to declare passenger absence from trip detail
This mr adds the ability for the driver to mark a passenger as absent directly from the trip detail screen. The driver taps the "Absent" button on a passenger row, selects trip direction (Outbound/Return), adds an optional observation, and confirms. The absence is recorded immediately via POST /api/absence/createPassengerAbsence with reportedBy=CHAUFFEUR and state=Processed.