Conflicts:
- `app/javascript/mastodon/load_locale.js`:
The file moved to `app/javascript/mastodon/locales/load_locale.ts`.
Ported the changes there and deleted `app/javascript/mastodon/load_locale.js`.
- `app/javascript/mastodon/locales/index.js`:
The file moved to `app/javascript/mastodon/locales/index.ts`.
Did *not* port the changes as I want to try something a bit different.
