function updatePipelineSink() {
    const sinkType = sinkSelector.options[sinkSelector.selectedIndex].value;
    console.log(`[UI] Selected sink: ${sinkType}`);
    switch (sinkType) {
      case 'video':
        pipeline.updateSink(new VideoSink());
        break;
      case 'pc':
        pipeline.updateSink(new PeerConnectionSink());
        break;
      default:
        alert(`unknown sink ${sinkType}`);
        break;
    }
  }
Updates the pipeline based on the current settings of the sinkSelector UI
element.