13,689 new quiz questions in 160 practice islands (grades 3-12), Question.figure, replay rotates the quiz, LaTeX removed from lesson/question text

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

content/tests_node_completion.py

@@ -231,3 +231,37 @@ class NodeQuizCompleteTests(TestCase):
 
         self.assertEqual(body['stats']['progressPercent'], 10.0)  # ۱ از ۱۰ درس
         self.assertTrue(UserLessonCompletion.objects.filter(user_id=self.user.id).exists())
+
+
+class NodeQuizRotationTests(TestCase):
+    """دوباره‌بازیِ یک جزیره آزمونِ تازه می‌دهد؛ رفرش تا پایانِ آزمون همان را می‌دهد."""
+
+    def setUp(self):
+        cache.clear()
+        grade = Grade.objects.create(title='پایه نهم', icon='', color='')
+        unit = Unit.objects.create(grade=grade, title='فصل ۱', order=1)
+        self.node = Node.objects.create(unit=unit, title='اول', order=1)
+        for i in range(4):
+            lesson = Lesson.objects.create(node=self.node, title=f'درس {i}')
+            for j in range(12):
+                question = Question.objects.create(
+                    lesson=lesson, type='multiple_choice', prompt=f'سوال {i}-{j}')
+                Choice.objects.create(question=question, value='الف', is_correct=True)
+                Choice.objects.create(question=question, value='ب', is_correct=False)
+        self.user = User.objects.create(phone='09120000019', grade_id=grade.id)
+        self.auth = {'HTTP_AUTHORIZATION': f'Bearer {issue_access_token(self.user.id)}'}
+
+    def _ids(self):
+        body = self.client.get(f'/api/nodes/{self.node.pk}/quiz', **self.auth).json()
+        return [q['id'] for q in body['questions']]
+
+    def test_refresh_keeps_the_quiz_until_it_is_completed(self):
+        self.assertEqual(self._ids(), self._ids())
+
+    def test_each_completed_round_draws_a_fresh_quiz(self):
+        first = self._ids()
+        UserNodeCompletion.objects.create(
+            user_id=self.user.id, node=self.node, correct_count=4, total_questions=4, stars=3)
+        second = self._ids()
+        self.assertNotEqual(first, second)
+        self.assertEqual(second, self._ids())