{
  "books": [
    {
      "id": 1,
      "title": "کتاب ریاضی کاتالوگ",
      "code": "MATH-CAT-BOOK",
      "grade_level_id": 3,
      "is_active": true
    }
  ],
  "chapters": [
    {
      "id": 1,
      "curriculum_book_id": 1,
      "title": "فصل کاتالوگ",
      "order": 1,
      "topics": [
        {"id": 1, "title": "مبحث کاتالوگ", "order": 1}
      ]
    }
  ],
  "subject_books": [
    {"subject_id": 1, "curriculum_book_id": 1}
  ]
}
