Add related information to typst diagnostics

[NickAcPT]

Adds related information to the diagnostics based on the trace points provided by typst itself.

This is my first time interacting with this codebase so if you spot anything that could be improved, please do let me know!

Before the change:

After the change:

[nvarner]

This looks great, thank you! Pending the GH Actions checks, I'd tentatively like to merge.

I tend to write Rust in a functional style, so the biggest code improvement to match the rest of the code base would be to adopt that kind of approach and use iterators/streams where possible. That said, it's not essential, and gets difficult when you have streams with Result and Option (as you do), so it's not a particularly big deal.

Overall, code looks good, split into reasonable and codebase-idiomatic functions.

[nvarner]

@NickAcPT can you fix the clippy errors? I'd be happy to merge after that

[NickAcPT]

@nvarner whooosies! I forgot to run clippy, my bad.
I'll fix it as soon as I can and I'll let you know! 👍

[NickAcPT]

@nvarner Apologies for not fixing it sooner!
I think it should be good to go, please let me know if there's anything else you'd want me to fix. ^-^

[nvarner]

No big deal. Looks good now. Thanks for the improvements!