Looks like the version of Prettier I just installed is v3, whereas our
last run in the impress-2020 repo was with v2. I don't think we had any
special config in that project, I think these are just changes to
Prettier's defaults, and I'm comfortable accepting them! (Mostly seems
like a lot of trailing commas.)
We add jsbuilding-rails to get esbuild running in the app, and then we copy-paste the files we need from impress-2020 into here!
I stopped at the point where it was building successfully, but it's not running correctly: it's not sure about `process.env` in `next`, and I think the right next step is to delete the NextJS deps altogether and use React Router instead.
