wrapped custom widget items in containers so we have more control of the surrounding, i.e. divider

Hyperbar.Windows.MediaController/MediaControllerWidgetView.xaml.cs

@@ -0,0 +1,8 @@
+using Microsoft.UI.Xaml.Controls;
+namespace Hyperbar.Windows.MediaController;
+
+public sealed partial class MediaControllerWidgetView : 
+    UserControl
+{
+    public MediaControllerWidgetView() => InitializeComponent();
+}