/// Attachment crypto context for BG attachment read/write operations.
///
/// This data container carries the resolved channel cipher sequence and the
/// key-schedule-enriched cipher parameters so attachment crypto calls can use
/// one consistent context.
class AttachmentCryptoContext {
  /// Ordered cipher chain applied by CCC for this attachment operation.
  final List<int> cipherSequence;

  /// Effective cipher parameters, including key-schedule metadata.
  final Map<String, dynamic> cipherParams;

  const AttachmentCryptoContext({
    required this.cipherSequence,
    required this.cipherParams,
  });
}