[SUGGESTION] roslyn services in custom extension

From vscode-dotnettools created by [sapsari](https://github.com/sapsari): microsoft/vscode-dotnettools#827

### Describe the feature you'd like

I want to develop a VS Code extension built on C# Dev Kit, like [Unity](https://marketplace.visualstudio.com/items?itemName=visualstudiotoolsforunity.vstuc#review-details)

Is it possible to export and use Roslyn services DiagnosticAnalyzer, CodeFixProvider, CompletionProvider, CodeRefactoringProvider or IAsyncCodeLensDataPointProvider? Or is it planned to support them in the near future?

If so, is it possible to use a Roslyn workspace provided by C# Dev Kit, like VisualStudioWorkspace in VS?

I have a VS extension [*](https://marketplace.visualstudio.com/items?itemName=MerryYellow.UCA-Lite) that I want to port to VS Code if possible. All the Roslyn providers listed above are in .NET Standard2.0 library dlls

Any kind of documentation, sample project or similar project is highly appreciated

### Alternatives considered

_No response_

### Environment Information

_No response_