The same app which is used by iD editor.

Organization is already created: https://app.transifex.com/osmapp/osmapp/dashboard/

We need to:

• move non-english files to transifex
• add yarn script for fetching the translations
• add github action which commits the new files / or opens a PR (whatever is easier)
• create a yarn script for getting new translations keys from code and pushing it to Transifex

see https://github.com/openstreetmap/iD/blob/develop/scripts/update_locales.js