[dev-v5] Fix MCP Package Sign Issue

Author: dvoituron

src/Tools/McpServer/Microsoft.FluentUI.AspNetCore.McpServer.csproj

@@ -104,6 +104,10 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.Components.Web" />
     <PackageReference Include="Microsoft.Extensions.Hosting" />
+    <PackageReference Include="Microsoft.VisualStudioEng.MicroBuild.Core">
+	    <PrivateAssets>all</PrivateAssets>
+	    <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+	  </PackageReference>
   </ItemGroup>
 
   <!-- Reference to the FluentUI Components for API extraction (still needed for type information) -->