Added playing song view. Adding styling to playing song. Fixed caching cancellation issue.

Harmonia.WinUI/Views/PlayingSongView.xaml

@@ -0,0 +1,17 @@
+<UserControl
+    x:Class="Harmonia.WinUI.Views.PlayingSongView"
+    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:local="using:Harmonia.WinUI.Views"
+    xmlns:vm="using:Harmonia.WinUI.ViewModels"
+    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+    DataContext="{Binding Source={StaticResource Locator}, Path=PlayingSongViewModel}"
+    d:DataContext="{d:DesignInstance Type=vm:PlayingSongViewModel, IsDesignTimeCreatable=True}"
+    mc:Ignorable="d">
+    <Grid HorizontalAlignment="Center" VerticalAlignment="Center"  Margin="20">
+        <Image Source="{Binding SongImageSource, Mode=OneWay}" Stretch="Uniform">
+        </Image>
+        <Canvas Background="#19000000"></Canvas>
+    </Grid>
+</UserControl>