saveSecure static method
Saves bytes encrypted in the vault (key in Keychain/Keystore). await UFile.saveSecure("id-card", bytes). macOS: unsigned debug builds show a Keychain password prompt after each rebuild; Team-signed apps never do.
Implementation
static Future<void> saveSecure(String key, List<int> bytes) => UFileStorage.setBytes(key, bytes, bucket: UStorageBucket.vault);