Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-19T00:28:20+00:00	DMARC	—	VALID	`a7981cce702c…`
2026-08-19T00:28:20+00:00	SPF	—	VALID	`f39f188acbd5…`