Key points on questions link into article sections (AMBOSS-style) with samples; difficulty tagging with builder/bank filters; adaptive session algorithm prefers unanswered questions then recycles older incorrect ones, weakest categories first with damping; question create/edit is now admin/educator only; expired exams no longer auto-submit on resume; exam suspend messaging updated. Migrations k4f5a6b7c819, l5a6b7c8d920, m6a7b8c9d031. 63 backend and 97 frontend tests pass.
Questions support an explanation per option, edited in the question dialog and shown in study feedback. Keys must match current options. Migration j3e4f5a6b708. 60 backend and 95 frontend tests pass.
