fix: correct tojson|safe usage in templates and update validator

- Remove |safe from |tojson in HTML attributes (x-data) - quotes must
  become " for browsers to parse correctly
- Update LANG-002 and LANG-003 architecture rules to document correct
  |tojson usage patterns:
  - HTML attributes: |tojson (no |safe)
  - Script blocks: |tojson|safe
- Fix validator to warn when |tojson|safe is used in x-data (breaks
  HTML attribute parsing)
- Improve code quality across services, APIs, and tests

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/services/content_page_service.py

@@ -526,7 +526,9 @@ class ContentPageService:
         return (
             db.query(ContentPage)
             .filter(and_(*filters) if filters else True)
-            .order_by(ContentPage.vendor_id, ContentPage.display_order, ContentPage.title)
+            .order_by(
+                ContentPage.vendor_id, ContentPage.display_order, ContentPage.title
+            )
             .all()
         )