Delete questions

Delete up to BATCH_MAX_ITEMS questions in a single request (CASCADE soft-delete).

A question is homed under a quiz XOR a question bank, so the write route accepts either quizzes:write OR question-banks:write (OR logic). Each item is a resource-identifier object ({type, id}). Per item the question is resolved org-scoped + live (already-deleted / wrong-org / malformed ids surface as per-item not_found) and, in that item's own atomic block, the question's answers are SOFT-deleted and then the question itself is SOFT-deleted. The parent quiz / question bank (and its other questions) are left untouched.

Within-batch duplicate detection is first-wins on id; each deleted item echoes the caller's input id. Response is 200 if all deleted, 207 if any failed, 400 if the envelope is empty or over the cap. See api_v2/docs/batch-responses.md for the envelope shape.

Required OAuth scope: question-banks:write or quizzes:write