Replaces the offers linked to a broadcast with the supplied set (a full replace, not an incremental add) -- linking drives offer reporting and revenue attribution. offer_uuids is the broadcast's complete linked set: exactly these offers, nothing else. Omit or send [] to unlink all of them. Every UUID must belong to an offer in the authenticated account -- if any one does not, the request is rejected with 422 and the broadcast keeps the offers it already had. no_offer marks the broadcast as deliberately promoting no offer; it only holds when offer_uuids is empty. The response returns each linked offer with the variable that carries that offer's link in the message body. offer_links sets per-offer link parameter rows; send rows: null for an entry to reset that offer to the defaults.