List appointments for the locations the token can access, oldest change first.

since is an inclusive (>=) filter on updatedAt, the time the appointment record last changed. order sorts by updatedAt and defaults to asc.

A cursor carries the since, order and locationUid of the listing it came from, so send it alone; any of those sent alongside it are ignored. Follow nextCursor until it is null before advancing since: since is inclusive and updatedAt values are not unique, so moving the watermark mid-traversal skips records sharing the boundary timestamp.

Required scope: read_appointments.