Return a page of colleagues in the caller's own account — people who already have their own account and can be picked as the traveler for a booking made on their behalf. Optional query is a case-insensitive substring of the stored full name, applied upstream before pagination. This list is never cached or stored locally.

With bookingId, people already travelling on that train booking are left out of each page (so a page can hold fewer than limit items while nextOffset still advances), and a carnet booking lists only people matching its invoice profiles and returns personCreationAvailable: false.