Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-21T14:22:53+00:00	DMARC	—	VALID	`1da5eba8a3e2…`
2026-08-21T14:22:53+00:00	SPF	—	VALID	`0dfb80bce2a4…`