Handle mc and fr questions as ref

[johnarban]

This PR refactors the Multiple Choice and Free Response questions to be nested dictionaries that are updated using Refs. This PR also makes sure the stage they belong to is a part of the question so they can be distinguished in the dashboard.

The general sequence is

free_responses = Ref(local_state.fields.free_responses).value.copy()['responses']
// do something ot the free responses
Ref(local_state.fields.free_responses).set({'responses': free_responses})

The .copy() seems necessary to prevent sharing modifications to free_response or 'mc_scoring` with other users. the mc and fr questions no longer have Pydantic models associated with them.

[nmearl]

This is looking good to me. But I haven't tried without @Carifio24's quick fix. Can you give this a shot after removing Jon's changes and see if you fix pre-filled FR or MC questions in two different app instances?

[johnarban]

This is looking good to me. But I haven't tried without @Carifio24's quick fix. Can you give this a shot after removing Jon's changes and see if you fix pre-filled FR or MC questions in two different app instances?

@nmearl , I ran it with the commits on cosmicds/cosmicds#361 removed. The free-response and mulitple choice questions were not shared between sessions for two different users run on a single solara server instance

[nmearl]

Excellent -- looks good to me then!

[patudom]

Great, thanks @johnarban & @nmearl. Do we still need cosmicds/cosmicds#361 or do we want to undo those?

[patudom]

And do we want to bring this over to the demo branch, or should we leave that alone since we know it works?