Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-20T04:01:15+00:00	DMARC	—	VALID	`6a6dbc137282…`
2026-08-20T04:01:15+00:00	SPF	—	VALID	`b8212d2f2f08…`