Simpler work directory

Currently, for each environment, the working directory looks like:

/build/vite/dev/
  node_modules/
  kotlin/
  vite.config.js

Currently, Vite is ran from the kotlin/ plugin, but this makes a bunch of things weird, as this isn't where the vite.config.js file is.

We should investigate where we can combine everything into a single directory, and have Vite run directly in the same directory as its config.