Verify Views files against decompiled, extract embedded types

Fixed files:
- SkiaImageButton.cs: Added SVG support with multi-path search
- SkiaNavigationPage.cs: Added LinuxApplication.IsGtkMode check
- SkiaRefreshView.cs: Added ICommand support (Command, CommandParameter)
- SkiaTemplatedView.cs: Added missing using statements

Extracted embedded types to separate files (matching decompiled pattern):
- From SkiaMenuBar.cs: MenuBarItem, MenuItem, SkiaMenuFlyout, MenuItemClickedEventArgs
- From SkiaNavigationPage.cs: NavigationEventArgs
- From SkiaTabbedPage.cs: TabItem
- From SkiaVisualStateManager.cs: SkiaVisualStateGroupList, SkiaVisualStateGroup, SkiaVisualState, SkiaVisualStateSetter
- From SkiaSwipeView.cs: SwipeItem, SwipeStartedEventArgs, SwipeEndedEventArgs
- From SkiaFlyoutPage.cs: FlyoutLayoutBehavior (already separate)
- From SkiaIndicatorView.cs: IndicatorShape (already separate)
- From SkiaBorder.cs: SkiaFrame
- From SkiaCarouselView.cs: PositionChangedEventArgs
- From SkiaCollectionView.cs: SkiaSelectionMode, ItemsLayoutOrientation
- From SkiaContentPresenter.cs: LayoutAlignment

Verified matching decompiled:
- SkiaContextMenu.cs, SkiaFlexLayout.cs, SkiaGraphicsView.cs

Build: 0 errors

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Services/HighContrastService.cs

@@ -348,55 +348,3 @@ public class HighContrastService
         }
     }
 }
-
-/// <summary>
-/// High contrast theme types.
-/// </summary>
-public enum HighContrastTheme
-{
-    None,
-    WhiteOnBlack,
-    BlackOnWhite
-}
-
-/// <summary>
-/// Color palette for high contrast mode.
-/// </summary>
-public class HighContrastColors
-{
-    public SKColor Background { get; set; }
-    public SKColor Foreground { get; set; }
-    public SKColor Accent { get; set; }
-    public SKColor Border { get; set; }
-    public SKColor Error { get; set; }
-    public SKColor Success { get; set; }
-    public SKColor Warning { get; set; }
-    public SKColor Link { get; set; }
-    public SKColor LinkVisited { get; set; }
-    public SKColor Selection { get; set; }
-    public SKColor SelectionText { get; set; }
-    public SKColor DisabledText { get; set; }
-    public SKColor DisabledBackground { get; set; }
-}
-
-/// <summary>
-/// Event args for high contrast mode changes.
-/// </summary>
-public class HighContrastChangedEventArgs : EventArgs
-{
-    /// <summary>
-    /// Gets whether high contrast mode is enabled.
-    /// </summary>
-    public bool IsEnabled { get; }
-
-    /// <summary>
-    /// Gets the current theme.
-    /// </summary>
-    public HighContrastTheme Theme { get; }
-
-    public HighContrastChangedEventArgs(bool isEnabled, HighContrastTheme theme)
-    {
-        IsEnabled = isEnabled;
-        Theme = theme;
-    }
-}