Bulk-create actors with linked users and hosts from flat rows. A spreadsheet format is recommended for identity data (one row per person or endpoint).Rows that resolve to the same user identity (email, username, or endpoint UID) mergeinto a single actor. Optional description on each row is stored on the actor andused by automated agents together with the actor's risk_level.Hosts are matched by endpoint_uid only; host_name does not merge hosts across rows.