GRO-682 - 3 - Clean up obviously unused packages/files

[bpander]

Last bit of GRO-682: Initial cleanup + prep

1. Removes nonfunctional "frontend" stuff
   a. E.g. astro will use a build script, but package.json already has a build script but it doesn't do anything. I also removed some other "frontend" stuff to make it clearer that astro is The Frontend.
2. Removes useless jest tests
   a. We'll have unit tests with astro but probably won't use jest. Also the unit tests seem safe to remove because:
   • nothing runs them and they haven't worked in over a year
   • most of what they test isn't used in this repo at all
   • some don't test anything meaningful, they just test functions defined in the tests themselves :jackiechan_wtf:
3. Removes some packages obviously not used anymore. We clearly aren't using grunt, mocha, or chai for example.

There's still a lot more than can be cleaned up in this repo, but I'd like to focus on the obvious, high priority stuff for now. Docs is still very much a Rube Goldberg machine, and I'm afraid of knocking out something load-bearing.

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How to verify

The critical functionality is all in .github/workflows and amplify.yml. As long as that all still works, we should be good to go.

So it's mainly script/docs, script/build, script/links and bun lint-*.

Here's the successful amplify deployment: https://us-east-1.console.aws.amazon.com/amplify/apps/dkkh35gceu2po/branches/gro-682-initial-cleanup-3/deployments

[tmashara]

looks good, thank you for cleaning things up!

[tmashara]

nit: it seems like we don't need this package as well

[bpander]

Legit, removed in cb6cef2