This is an important workflow for people doing art stuff, I'm told! They used to use the Classic DTI broken image UI for this, but now that that's uhh Fully Gone, let's add this more explicitly!
We never had a specific reason why we didn't use the router for this I don't think? Not that I wrote down anyway. Let's just switch it over and see what happens!
I mainly did this as a misdiagnosis of the page reload problem fixed in c162864, but it seems like a good idea to try out anyway!
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.