Output Server Stats through LSP API

[rchl]

This code should ideally not use console.log as that's not gonna work when server communicates with the client using stdio. Using console.error instead would work but possibly better to just use connection.console.* API. Maybe also print everything in one go instead of in separate log calls.

https://github.com/johnsoncodehk/volar/blob/e1514295e44b1efbb13f8656106530504a9f51e3/packages/language-server/src/features/customFeatures.ts#L12-L67