該級播到第 18 類結束時，書籤項目仍要留著

[Aiuanyu]

• 該項仍佔位，免得同步書籤項目被先前同級進度取代
• 顯示為「○○級全部放送煞，重新開始？」，點選就從 1-1 重新開始

[google-labs-jules]

Jules is on it. When finished, you will see another comment and be able to review a PR.

[google-labs-jules]

I apologize, but I encountered an unexpected error and wasn't able to complete the task.

[google-labs-jules]

Ready for a review! A PR has been created.