{"node_id":"aethelon-node-1","key_id":"kcaed1f6a5dcc","algorithm":"ed25519","public_key_b64":"GTRy38F8uuMA3zl1qUSrGH3ofO+Dcflez5+2pOqB/YE=","receipt_spec":"mesh-receipt/0.1","verify":"sha256 canonical-JSON payload (sorted keys, no spaces) → verify ed25519 signature over the canonical bytes"}