refactor: redesign admin permalinks to RESTful paths

- Replace fragile /admin/ai-playground and /admin/ai-generation routes
  with item-scoped /admin/questions/{id}/generate endpoints
- Add /admin/tryouts/{id}/questions route using Tryout primary key
  instead of composite query params (?tryout_id=X&website_id=Y)
- Fix variant detail and review-bulk endpoints to use scoped paths
- Update all internal links (dashboard, hierarchy, exams) to new routes
- Remove obsolete ai_playground_view/submit/save functions

app/services/ai_generation.py

@@ -107,6 +107,7 @@ REQUIREMENTS:
 4. Only ONE correct answer
 5. Include a clear explanation of why the correct answer is correct
 6. Make the question noticeably {level_desc} - not just a minor variation
+7. Follow and preserve any HTML formatting (e.g., <p>, <br>, <b>) present in the basis question
 
 OUTPUT FORMAT:
 Return ONLY a valid JSON object with this exact structure (no markdown, no code blocks):