toJson method
Serializa para Map<String, dynamic>. Nunca inclui chave.
envelope.toJson();
// {'version': 2, 'algorithm': 'chacha20-poly1305', 'ciphertext': '...', ...}
Implementation
Map<String, dynamic> toJson() => {
'version': version,
'algorithm': algorithm.value,
'ciphertext': base64.encode(ciphertext),
'nonce': base64.encode(nonce),
'tag': base64.encode(tag),
'aad': base64.encode(aad),
};