Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-19T09:15:44+00:00	DMARC	—	VALID	`d5ec7e9a4253…`
2026-08-19T09:15:44+00:00	SPF	—	VALID	`58fda1572c4f…`