CLaSP: Create CLaSP.VS
CLaSP intentionally omits any depiction of the classes described in the LSP specification to keep things flexible and widely available. IMO this has achieved its goals WRT flexibility, but it does restrict us from providing some convenience and quality of life items that people have requested such as default implementations of the initialize and initialized Handlers, abstract classes for endpoints described in the specification and more.
We can perhaps have our cake and eat it too by creating a package that's something like Microsoft.CommonLanguageServerProtocol.Framework.VisualStudio which references CLaSP and Microsoft.VisualStudio.LanguageServer.Protocol as a set of convenient default implementations and expansions on top of CLaSP. CLaSP would still be where anything which doesn't directly deal with LSP Spec elements would go, but we can provide a smoother ride for people implementing in VS since we understand their needs well.