UI: Only allow right click to create a context menu if a game is selected.

src/Ryujinx/UI/Controls/ApplicationListView.axaml

@@ -7,7 +7,6 @@
     xmlns:helpers="clr-namespace:Ryujinx.Ava.UI.Helpers"
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
     xmlns:ui="clr-namespace:FluentAvalonia.UI.Controls;assembly=FluentAvalonia"
-    xmlns:converters="clr-namespace:Avalonia.Data.Converters;assembly=Avalonia.Base"
     d:DesignHeight="450"
     d:DesignWidth="800"
     Focusable="True"
@@ -16,7 +15,6 @@
     x:DataType="viewModels:MainWindowViewModel">
     <UserControl.Resources>
         <helpers:BitmapArrayValueConverter x:Key="ByteImage" />
-        <controls:ApplicationContextMenu x:Key="ApplicationContextMenu" />
     </UserControl.Resources>
     <Grid>
         <Grid.RowDefinitions>
@@ -28,10 +26,10 @@
             Padding="8"
             HorizontalAlignment="Stretch"
             VerticalAlignment="Stretch"
-            ContextFlyout="{StaticResource ApplicationContextMenu}"
+            SelectedItem="{Binding ListSelectedApplication}"
+            ContextFlyout="{Binding ListAppContextMenu}"
             DoubleTapped="GameList_DoubleTapped"
-            ItemsSource="{Binding AppsObservableList}"
-            SelectionChanged="GameList_SelectionChanged">
+            ItemsSource="{Binding AppsObservableList}">
             <ListBox.ItemsPanel>
                 <ItemsPanelTemplate>
                     <StackPanel