RdXmlFile for single file mode?

[stevefan1999-personal]

I needed this:

<ItemGroup>
  <RdXmlFile Include="rd.xml" />
</ItemGroup>

so I tried this

#:rd rd.xml 

but it seems like it does not work yet:

> dotnet run test.cs

Unrecognized directive 'rd' at F:\dotnet\test-avalonia\test.cs:15.