Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-19T03:35:58+00:00	DMARC	—	VALID	`9b3a3a7ec67e…`
2026-08-19T03:35:58+00:00	SPF	—	ABSENT	`b081350f91db…`