List my favorites

Runs user.listFavorites for one entityType (default hotel), newest first, one entry per hotel. Returns { entityIds, items }: items are { entityType, entityId, hotelKey, ref, name, imageUrl, city, country, starRating } where entityId equals hotelKey for a supplier hotel. ref is freshly minted on every response and opens GET /v1/hotels/{ref}; it is null when the row cannot mint one. The display fields are the snapshot the client sent when it saved the row, and are null for rows saved before snapshots existed (render a placeholder; never fail). Each item also has savedAt. entityIds lists the same entries' ids, in order.