{"keys":[],"note":"Ed25519. Receipts sign `harmwise-receipt-v1\\n<record_id>\\n<system_id>\\n<seq>\\n<self>\\n<occurred_at>`; attestations sign their own JSON without `signature`, re-serialised with two-space indentation; published heads sign `harmwise-heads-v1\\n<date>\\n<root>\\n<count>`."}