The long term strategy for question representation should be to have all questions with a json representation.
Getting the json format documented is a good first step.
The second step would be to write code for processing the runestone manifest that could take the PreTeXt representation of a question and create the json for the database. This will require work on both the PreTeXt side to provde the PreTeXt source as well as on our side to convert the PreTeXt source to json.