Authentication history

Immutable persisted observations.

Observed	Signal	Selector	Verdict	Fingerprint
2026-08-18T14:50:04+00:00	DMARC	—	VALID	`a7db65ed7967…`
2026-08-18T14:50:04+00:00	SPF	—	VALID	`8d0066577c19…`