tutor-v7-diagram-kit: anchor short follow-ups to the previous question, new diagram pieces in the prompt

A real chat answered "what if 6 were 4?" with a semicircle problem from the
retrieved book excerpt instead of the parabola asked a moment before. A short
follow-up now carries the previous user question next to it. The catalog
teaches line equations as written, regularPolygon, exteriorAngle, graphs only
through function items and tangents through tangent; fraction words (یک‌پنجم،
نُه‌دهم) pull the fraction section.

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

rag/tests_tutor_quality.py

@@ -106,7 +106,9 @@ class TutorPromptTests(SimpleTestCase):
         self.assertEqual(messages[0]['role'], 'system')
         self.assertEqual(len(messages), 1 + HISTORY_TURNS + 1)
         self.assertEqual(messages[-2], {'role': 'assistant', 'content': 'جواب 9'})
-        self.assertTrue(messages[-1]['content'].endswith('سوالِ دانش‌آموز: نفهمیدم'))
+        self.assertIn('سوالِ دانش‌آموز: نفهمیدم', messages[-1]['content'])
+        # سوالِ کوتاهِ ادامه‌ای به سوالِ قبلیِ همان گفتگو لنگر می‌شود
+        self.assertIn('سوالِ قبلیِ دانش‌آموز: «سوال 8»', messages[-1]['content'])
         self.assertIn('متنِ کتاب', messages[-1]['content'])
 
     def test_reasoning_models_get_no_temperature(self):