Caching of generated questionnaires

[nsenave]

Currently, if a user visualizes a questionnaire in the same mode several times in a row, an Eno call is made each time and the whole generation process is done entirely.

If the questionnaire hasn't changed, it would be nice to re-use the output that was previously generated.

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Note: there is an issue with the current design of the visualization feature. Example:

1. User A clics "Visualize -> Web"
2. User B clics "Visualize -> Interviewer"
3. User A refreshes the visualization tab

=> The Lunatic questionnaire passed to the orchestrator of the user A is the one that has been generated for the user B. 🫤

[nsenave]

Créer une issue pour l'aspect problématique de la concurrence en visu.