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.
