message: fix volume streaming channel visibility
diff: @@ -276,10 +276,12 @@ const VolumeStreamingVisual = PluginStateTransform.BuiltIn({
  // TODO: is this correct behavior?
  if (!channel) return StateTransformer.UpdateResult.Unchanged;
  + const visible = b.data.repr.state.visible;
  const params = createVolumeProps(a.data, newParams.channel);
  const props = { ...b.data.repr.props, ...params.type.params };
  b.data.repr.setTheme(Theme.create(plugin.representation.volume.themes, { volume: channel.data }, params));
  await b.data.repr.createOrUpdate(props, channel.data).runInContext(ctx);
  + b.data.repr.setState({ visible });
  b.data.sourceData = channel.data;
  // TODO: set the transform here as well in case the structure moves?
  