Update with recovered code from VM binaries (Jan 1)

Recovered from decompiled OpenMaui.Controls.Linux.dll:
- SkiaShell.cs: FlyoutHeader, FlyoutFooter, scroll support (918 -> 1325 lines)
- X11Window.cs: Cursor support (XCreateFontCursor, XDefineCursor)
- All handlers with dark mode support
- All services with latest implementations
- LinuxApplication with theme change handling

Hosting/ScopedLinuxMauiContext.cs

@@ -0,0 +1,17 @@
+using System;
+
+namespace Microsoft.Maui.Platform.Linux.Hosting;
+
+public class ScopedLinuxMauiContext : IMauiContext
+{
+	private readonly LinuxMauiContext _parent;
+
+	public IServiceProvider Services => _parent.Services;
+
+	public IMauiHandlersFactory Handlers => _parent.Handlers;
+
+	public ScopedLinuxMauiContext(LinuxMauiContext parent)
+	{
+		_parent = parent ?? throw new ArgumentNullException("parent");
+	}
+}