Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-19T07:11:09+00:00	DMARC	—	VALID	`5ca8c4679c78…`
2026-08-19T07:11:09+00:00	SPF	—	VALID	`81e19e851b36…`