Use case

At the moment we validate that the language of the description of an exercise is
correct only when the complete exercise is submitted, which is awkward since the
user then has to jump back to the initial page. Ideally, we would like to
validate it as soon as the description is edited (the user tries to navigate to
the next page).

See Step3Description and Step4Translation. There is a stub in
AddExerciseProvider, validateLanguage that sends the request to the backend.

Proposal

No response

Additional Context

No response