[WIP] Add language server support

[amckinney]

This adds support for the recently released https://github.com/bufbuild/buf-language-server.

This is based on the VSCode Language Extension Guide and the sample language server client implementation.

[amckinney]

All of the build errors originate from node_modules/vscode-languageclient/..., but we exclude node_modules in tsconfig.json- there's probably something small we need to adjust here.

[timostamm]

The build errors stem from tsc validating the types in dependencies with the compiler option strict: true. The package vscode-languageclient was written against @types/vscode v1.67.0, but we install v1.63.0.

The immediate issue is fixed with npm i @types/[email protected], but we might want to look into moving away from the deprecated vscode-test package long term.

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[scbizu]

Is this PR still alive ? From vscode-proto3 to buf , the go to definition is broken .

[nicksnyder]

No, the language server at https://github.com/bufbuild/buf-language-server is not being actively developed so this PR isn't going to get merged.