Handling broken grammar in builds through recovery and scope

[RoloEdits]

We have had some recent issues involving grammar failing to be fetched/build that then prevents helix from being able to build: #15419 #15405 . I think by default these should be logged, but recoverable and not block the compilation/install process.

Naively, we can just continue through the grammar fetching/builds and then build up the errors and return to just log. We could also use this time to use gix itself for clones, instead of shellng out to the git client. I believe the gix repo include a clone example?

In addition to this more fundamental change, there could also be a new config option that would enable the grammar the user wants built. This would lower disk space, something that has been brought up before, but just as a side effect. If we reduce the surface area of the grammars being built, we should be able to lower end user impact for other issues that could come up.

[editor]
grammar = ["rust", "python", "markdown"]

[the-mikedavis]

There is use-grammars in the languages.toml file that can be used to select a few grammars https://docs.helix-editor.com/master/languages.html#choosing-grammars