Last commit before separate repos work

This marks the last commit since the backend broke off from the combined
frontend/backend repository.

After this point, commits were made to the separated repo.

This is an exact record of the command used to filter out the frontend
from the combined repo, leaving only this backend repo:
../git-filter-repo --path package.json --path tsconfig.json --path
yarn.lock --path .prettierrc.js --path .eslintrc.json --path-regex
'^app\/javascript\/(?:(?<!packs\/).)*$' --invert-paths

This was run with the git filter-repo
(https://github.com/newren/git-filter-repo) script, which was located in
the directory above ("..") in this case.
The current working directory was a freshly cloned copy of the `console`
repository.

Additionally, Git LFS objects had to be copied over after the repo
filtering, since I had forgotten to download them all before running the
script.
Next time, we could avoid doing this by running `git lfs fetch --all`
after cloning.