LSP: Preparations and Cleanup

[falko17]

Warning

Please do not delete the lsp branch yet, as I will keep working on it.

Summary

Just in time for Christmas, this prepares the code base for the upcoming integration of the Language Server Protocol into SEE (#686). Additionally, this should resolve license timeouts in the CI, which have recently quite often caused the pipeline to fail.

NuGetForUnity

This integrates NuGetForUnity into SEE, which makes it a lot easier to integrate NuGet packages into SEE without having to extract the package, update it, pull in dependencies, etc.
This additionally has the nice property of downsizing our repository, since only the package names are stored in the repository and the packages themselves are resolved locally.
I have removed all existing packages from the repository that we got from NuGet in the past (FuzzySharp, HtmlAgilityPack, XZCompression) and tracked them in NuGetForUnity.

Note

In the future, when we want to import NuGet packages into SEE, we should do it using the NuGet menu option at the top of Unity.

Other changes

• In preparation of Implement support for the Language Server Protocol #686, I have added the OmniSharp LSP Client and associated LSP data models.
  • Apparently, this also caused Microsoft's C# Language Analyzer to activate, which caused a few additional diagnostics and warnings to be shown. I fixed these warnings, which were mainly about async methods' names having to end in Async (such that they are not easily overlooked, as they have to be awaited). These fixes account for the majority of changes in this pull request.
• I have cleaned up the CodeWindow (and related classes) and removed all multiplayer and editing capabilities, such as the CRDT. The reason is that 1) it currently does not work and makes the game freeze up, 2) it causes the code to be vastly more complex and less maintainable, and 3) when it did work, it worked neither reliably nor with good performance (due in part to our implementation and in part due to TextMeshPro complexities). If we want this capability back in the future, we should probably rewrite it.
• The CI scripts have been updated to hopefully cause less trouble when running the tests and creating the builds. Previously, they would often time out, causing many false positives – this should now be fixed.

[github-actions]

There are a few bad patterns I found which you should check.

[koschke]

@falko17 Well timed indeed.

[falko17]

Unfortunately, the new build script versions still cause some trouble with permissions I have to fix before this can be merged.

[falko17]

Unfortunately, the new build script versions still cause some trouble with permissions I have to fix before this can be merged.

Fixed it just in time for actual Christmas Day. This is now ready to review and merge. As it turned out, the problem was a bug in our Unity CI runner. I submitted a pull request that fixes the bug, and switched our pipeline to use my local fork for now.

[msteinbeck]

In preparation of #686, I have added the OmniSharp LSP Client and associated LSP data models.

@m4xxed has some experience with this LSP client.

[falko17]

@m4xxed has some experience with this LSP client.

Ah, good to know, thanks!

[koschke]

Looks good to me. Only one clarification question and one documentation request.

[koschke]

All things addressed. Good to go.