docs: add debugging/troubleshooting guide

[nettybun]

What's the problem this PR addresses?

Closes #5085. Mentions #5156.

The rationale is: I was trying to migrate from Yarn v1 to Yarn Berry and ran into an error. There are no good docs for how to deal with a stacktrace: the lack of docs was uncomfortable as an end user. So I wrote some docs!

I'm not a docs writer but I took screenshots soooo hopefully it makes sense.

P.S I noticed you're not using Git LFS, so I just uploaded the images as-is since there's already a precedent for that. ...

How did you fix it?

N/A ...

Checklist

• [x] I have read the Contributing Guide. Yes and I added to it

• [x] I have set the packages that need to be released for my changes to be effective. N/A

• [x] I will check that all automated PR checks pass before the PR gets reviewed.