fix: replace Markdown.Avalonia.Tight with a fork since it's unmaintained

Author: Kryptos-FR

sources/Directory.Packages.props

@@ -106,7 +106,7 @@
     <PackageVersion Include="Avalonia.Themes.Fluent" Version="$(AvaloniaVersion)" />
     <PackageVersion Include="Xaml.Behaviors.Avalonia" Version="$(AvaloniaBehaviorVersion)" />
     <PackageVersion Include="Xaml.Behaviors.Interactions" Version="$(AvaloniaBehaviorVersion)" />
-    <PackageVersion Include="Markdown.Avalonia.Tight" Version="11.0.2" />
+    <PackageVersion Include="ClassIsland.Markdown.Avalonia.Tight" Version="11.0.3.4" />
     <PackageVersion Include="CommunityToolkit.Mvvm" Version="8.2.2" />
   </ItemGroup>
   <!-- Windows/WPF dependencies -->

sources/presentation/Stride.Core.Presentation.Avalonia/Stride.Core.Presentation.Avalonia.csproj

@@ -19,7 +19,7 @@
     <PackageReference Include="Avalonia" />
     <!--Condition below is needed to remove Avalonia.Diagnostics package from build output in Release configuration.-->
     <PackageReference Condition="'$(Configuration)' == 'Debug'" Include="Avalonia.Diagnostics" />
-    <PackageReference Include="Markdown.Avalonia.Tight" />
+    <PackageReference Include="ClassIsland.Markdown.Avalonia.Tight" />
     <PackageReference Include="Xaml.Behaviors.Interactions" />
   </ItemGroup>