Switch to teal-language-server

[pdesaulniers]

WIP

This PR replaces the extension's built-in language server with teal-language-server.

[Hedwig7s]

It doesn't seem to update the checks until the file is saved (or otherwise is a bit inconsistent)
Also requires nil parameters to be filled (and since teal-language-server is supposed to have optional parameters for all types I'll assume is a bug here for now)

[ElhamAryanpur]

Is there any progress on this?

[pdesaulniers]

Hello! I haven't made any changes to this PR since last year. I'm not sure if it requires any changes, since it simply tells vscode-teal to load teal-language-server at startup: https://github.com/teal-language/vscode-teal/blob/e1ead6fabdfee119e2717c96764ce43142d643ba/client/extension.js

It is still at the "draft" state because, back then, there were still a few kinks to iron out in teal-language-server (type hints displaying incorrectly, autocompletion not triggering in some contexts, maybe some issues noted by @Hedwig7s, etc).

If you want to help with this, you can test the PR and report any issues that you find! It might also be a good idea to check how the language server behaves in a different text editor (such as Neovim) for comparison.

[ElhamAryanpur]

ohh okay, I'll look into it and report back my findings. Thank you!