Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-19T13:24:04+00:00	DMARC	—	VALID	`ce775e99a6aa…`
2026-08-19T13:24:04+00:00	SPF	—	VALID	`1ff73dcee55c…`