DotNetCampus.InkCanvas Avalonia 12 Compatibility Fork

This source is vendored from dotnet-campus/DotNetCampus.InkCanvas at commit e4383cadc3ae206dd96f5b72ba889a007ebc44fa, matching the DotNetCampus.AvaloniaInkCanvas 1.0.1 NuGet package previously used by the app.

The local project keeps the assembly name DotNetCampus.AvaloniaInkCanvas so the host code can continue using the existing namespaces and APIs.

Local compatibility changes:

Replace Avalonia 11 Visual.VisualRoot render scaling access with TopLevel.GetTopLevel(this)?.RenderScaling.
Reference Avalonia 12 packages from a local project instead of the Avalonia 11-targeted NuGet package.
Import the Avalonia 12 optional feature extension namespace for Skia custom drawing operations.