Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-16T21:05:23+00:00	DMARC	—	VALID	`f6d4e31192c6…`
2026-08-16T21:05:23+00:00	SPF	—	VALID	`80b67e724709…`