{"node_id":"aethelon-node-1","key_id":"k9f0c043a0400","algorithm":"ed25519","public_key_b64":"qJZHv9xcCs1TrJGJ6Yz7XZ4V6Tw9eDJAzmYH350vHak=","receipt_spec":"mesh-receipt/0.1","verify":"sha256 canonical-JSON payload (sorted keys, no spaces) → verify ed25519 signature over the canonical bytes"}