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

patch_css.py

@@ -0,0 +1,19 @@
+import re
+
+with open("app/admin_web.py", "r") as f:
+    content = f.read()
+
+# Fix activity feed CSS
+content = content.replace(
+    ".activity-feed li:last-child {{ border-bottom: none; }}",
+    ".activity-feed li:last-child {{ border-bottom: none; }}\n    .activity-feed li svg, .activity-feed li svg.nav-icon, .activity-feed li svg.huge-icon {{ width: 20px; height: 20px; flex-shrink: 0; }}"
+)
+
+# Fix alert CSS
+content = content.replace(
+    ".alert-warning {{ background: #fef3c7; border: 1px solid #f59e0b; color: #92400e; }}",
+    ".alert svg, .alert svg.huge-icon, .alert svg.page-icon {{ width: 24px; height: 24px; flex-shrink: 0; margin-right: 4px; margin-bottom: -4px; }}\n    .alert-warning {{ background: #fef3c7; border: 1px solid #f59e0b; color: #92400e; }}"
+)
+
+with open("app/admin_web.py", "w") as f:
+    f.write(content)