signWithPrivKey function
Signs the hashed data in messageHash using the given private key, also concats the public key at the end.
Implementation
Uint8List signWithPrivKey(Uint8List messageHash, Uint8List privateKey) {
_validateLength(privateKey, _privateKeyLength, 'privateKey');
final signedMsg = ed448Wallet.ed448Sign(privateKey, messageHash);
final publicKey = ed448Wallet.ed448DerivePublicKey(privateKey);
return Uint8List.fromList(signedMsg + publicKey);
}