Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-16T22:27:05+00:00	DMARC	—	VALID	`c9f33b8eba10…`
2026-08-16T22:27:05+00:00	SPF	—	VALID	`0bcaab2568ad…`