dispose method

Implementation

@override
void dispose() {
  if (_disposed) return;
  _disposed = true;
  _rawModeEnabled = false;
  _inputStreamSubscription?.cancel();
  _resizeStreamSubscription?.cancel();
  _shutdownStreamSubscription?.cancel();
  _inputController.close();
  _resizeController.close();
  scheduleMicrotask(() {
    if (!_shutdownController.isClosed) {
      _shutdownController.close();
    }
  });
}