Reads the speech text of the selected slides and generates quiz questions with an LLM.
Nothing is saved: the questions come back for the caller to place on slides (PATCH /videos/{videoId}). placeAfterSlideId on each quiz suggests where it belongs.
notice is non-null when fewer questions were produced than requested — the slides did not contain enough material. The feedbackContextId values are opaque, short-lived identifiers for the generation and can be ignored.
Requires the workspace to have LLM features enabled (409 otherwise).