Fix System Tray Menu to use new icons and include "Switch Group"

Author: chrisuthe

src/SendspinClient/App.xaml

@@ -33,8 +33,9 @@
                         <!-- Playback Controls -->
                         <MenuItem Header="{Binding IsPlaying, Converter={StaticResource PlayPauseTextConverter}}"
                                   Command="{Binding PlayPauseCommand}"/>
-                        <MenuItem Header="⏭ Next" Command="{Binding NextTrackCommand}"/>
-                        <MenuItem Header="⏮ Previous" Command="{Binding PreviousTrackCommand}"/>
+                        <MenuItem Header="▶▶ Next" Command="{Binding NextTrackCommand}"/>
+                        <MenuItem Header="◀◀ Previous" Command="{Binding PreviousTrackCommand}"/>
+                        <MenuItem Header="📡 Switch Group" Command="{Binding SwitchGroupCommand}"/>
                         <Separator/>
 
                         <!-- Volume Controls -->

src/SendspinClient/Resources/Converters/BoolToVisibilityConverter.cs

@@ -99,7 +99,7 @@ public class PlayPauseTextConverter : IValueConverter
     public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
     {
         var isPlaying = value is bool b && b;
-        return isPlaying ? "⏸ Pause" : "▶ Play";
+        return isPlaying ? "❚❚ Pause" : "▶ Play";
     }
 
     public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)