I was with you when you explained how you got them off of MS Word (even worse if it was the web version!!), until you brought up VSCode. I get it, you are probably advocating very practical choices. Just that I wouldn't recommend students to become dependent on VSCode (due to its vendor and "telemetry"). Basically, that makes the students again dependent on MS. But I guess since you recommend an extension, you cannot recommend VSCodium and adding the extension store as someone in a teaching position? If you can, then I would strongly advocate recommending VSCodium instead (or non-electron app editors), to avoid spyware on their machines and to promote a healthier tooling.

There is a language server for Typst: https://github.com/Myriad-Dreamin/tinymist

I have not tried this one, but the predecessor (typst-lsp) was working fine with Neovim for me when I did my little Typst experiment last year. Whatever the VSCode plugin is offering should be possible to replicate on top of tinymist.