[Feature request] Toggle to print Proof.Y

[callebtc]

It would be great to have a toggle that also prints the Proof.Y in the output JSON for a decoded token.

The Proof.Y can be calculated by computing hash_to_curve(secret) (see NUT-00). The hash_to_curve requires sha256 and secp256k1 (to check if the point is on the curve). An implementation in cashu-ts can be found here.