40 scenes, resuming at 0, model qwen2.5:3b-instruct
  10/40  12s  prefill 2s  gen 3s
  20/40  22s  prefill 4s  gen 6s
  30/40  33s  prefill 6s  gen 9s
  40/40  43s  prefill 8s  gen 12s
done: 40 summaries, 43s this session