feat(editor): Support nested configs

[nrayburn-tech]

Based off of #9739.

[graphite-app]

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[codspeed-hq]

CodSpeed Performance Report

Merging #9743 will not alter performance

_{Comparing nrayburn-tech:vscode-nested-config-support (8052ca5) with main (e408db8)}

Summary

✅ 33 untouched benchmarks

[nrayburn-tech]

Marking as draft until I can accommodate changes from #9760.

[Sysix]

I am sorry, I had not time this weekend to check if this works as expected :)
Will try to look into it the next days

[nrayburn-tech]

No rush. I was looking at implementing this for IntelliJ and it has me second guessing my approach.

Should the client be sending the initial configs that are found OR should the language server search the root_uri for this instead? I'm not sure how much filesystem access should be done from the language server, which is why I did it this way originally. Maybe it's a non-issue though.

[Sysix]

Should the client be sending the initial configs that are found OR should the language server search the root_uri for this instead?

My first idea was to do all the work on the server side, but after reading about the LSP Specification:

Servers are allowed to run their own file system watching mechanism and not rely on clients to provide file system events. However this is not recommended due to the following reasons:

• to our experience getting file system watching on disk right is challenging, especially if it needs to be supported across multiple OSes.
• file system watching is not for free especially if the implementation uses some sort of polling and keeps a file system tree in memory to compare time stamps (as for example some node modules do)
• a client usually starts more than one server. If every server runs its own file system watching it can become a CPU or memory problem.
• in general there are more server than client implementations. So this problem is better solved on the client side.

https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#workspace_didChangeWatchedFiles

Tested it today and it worked 🥳