Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-17T01:10:20+00:00	DMARC	—	VALID	`beb54e961fd8…`
2026-08-17T01:10:20+00:00	SPF	—	VALID	`a7b2df2ea3a5…`