Integrate with Vala sdk extension

[bilelmoussaoui]

Part of #75

[bilelmoussaoui]

I am waiting for the SDK to be published on flathub first, then give it a try with some Vala app

[SeaDve]

'vala', 'rust' etc. I guess should be its own type (e.g. type LanguageCode = 'vala' | 'rust')

[bilelmoussaoui]

'vala', 'rust' etc. I guess should be its own type (e.g. type LanguageCode = 'vala' | 'rust')

Right, ideally we would do the whole integration as an interface that gets implemented by the various integrations and we have some class that fetches all those integrations and enables them based on the SDK Type or something like that.

But that is more of a task I would keep for later then do as part of this merge request

[bilelmoussaoui]

I tried it locally and it seems to at least be running properly, the main issue is vls seems to be having issues to properly start vala-lang/vala-language-server#236 but that is unrelated to this.