Get a domain's Agent Authorization status

Whether the domain publishes an Agent Authorization (_agents) TXT record that lets agents on Primitive email it, read from DNS with the same engine the send path uses (an answer may be up to five minutes old): published (a record authorizes them), published_unauthorized (a record exists but does not), not_set_up (no record, the default) or inconclusive (the lookup could not tell; retry). The domain is one of the organization's, verified or pending; a credential confined to some mailboxes sees only the domains its scope covers. Needs domains:read.