docs: public String[] keypairZ85()
      {
          String[] pair = new String[2];
  
          byte[] publicKey = new byte[Size.PUBLICKEY.bytes()];
          byte[] secretKey = new byte[Size.SECRETKEY.bytes()];
  
          int rc = curve25519xsalsa20poly1305.crypto_box_keypair(publicKey, secretKey);
          assert (rc == 0);
  
          pair[0] = Z85.encode(publicKey, Size.PUBLICKEY.bytes());
          pair[1] = Z85.encode(secretKey, Size.SECRETKEY.bytes());
  
          return pair;
      }