feat: add demo, sync theme from scope.

demo/Ursa.Demo/ViewModels/MainViewViewModel.cs

@@ -47,6 +47,7 @@ public class MainViewViewModel : ViewModelBase
             MenuKeys.MenuKeyTagInput => new TagInputDemoViewModel(),
             MenuKeys.MenuKeyTimeline => new TimelineDemoViewModel(),
             MenuKeys.MenuKeyTwoTonePathIcon => new TwoTonePathIconDemoViewModel(),
+            MenuKeys.MenuKeyThemeToggler => new ThemeTogglerDemoViewModel(),
         };
     }
 }

demo/Ursa.Demo/ViewModels/MenuViewModel.cs

@@ -32,6 +32,7 @@ public class MenuViewModel: ViewModelBase
             new() { MenuHeader = "Pagination", Key = MenuKeys.MenuKeyPagination },
             new() { MenuHeader = "RangeSlider", Key = MenuKeys.MenuKeyRangeSlider, Status = "New"},
             new() { MenuHeader = "TagInput", Key = MenuKeys.MenuKeyTagInput },
+            new() { MenuHeader = "Theme Toggler", Key = MenuKeys.MenuKeyThemeToggler },
             new() { MenuHeader = "Timeline", Key = MenuKeys.MenuKeyTimeline, Status = "Updated" },
             new() { MenuHeader = "TwoTonePathIcon", Key = MenuKeys.MenuKeyTwoTonePathIcon, Status = "New"},
         };

demo/Ursa.Demo/ViewModels/ThemeTogglerDemoViewModel.cs

@@ -0,0 +1,6 @@
+namespace Ursa.Demo.ViewModels;
+
+public class ThemeTogglerDemoViewModel
+{
+    
+}