generateKey function
GenerateKey generates a public/private key pair using entropy from secure random.
Implementation
KeyPair generateKey() {
var seed = Uint8List(32);
fillBytesWithSecureRandomNumbers(seed);
var privateKey = newKeyFromSeed(seed);
var publicKey = privateKey.bytes.sublist(32, PrivateKeySize);
return KeyPair(privateKey, PublicKey(publicKey));
}