Demo mode: any non-empty signature is accepted. Replace with real Verus signer later.
ODINID: @demo#main
Challenge: _7qp_hxFMEFqpPNaMbllYw
Nonce: E9yqr7K6py1R8n2boccJU8XOOtH8Arua
Expires in: 300s
Scan the QR with your ODINID signer to produce a signature for the nonce.