Return which manage actions the train operator allows on an issued train booking, with the legs and travelers each one may apply to. Leg and traveler identifiers are the legId and travelerId values from GET /v1/trains/bookings/{id}.

state is processing while the booking or a previous operation on it has not settled, and none_available when the booking is not issued or the operator allows nothing. Each answer is read live from the operator and never cached.