Add secret management guide, client-side performance monitoring, and search accessibility enhancements

- Introduced a comprehensive Secret Management Guide detailing best practices, secret classification, development setup, production management, rotation procedures, and emergency protocols.
- Implemented a client-side performance monitoring script to track various metrics including page load performance, paint metrics, layout shifts, and memory usage.
- Enhanced search accessibility with keyboard navigation support for search results, ensuring compliance with WCAG standards and improving user experience.

backend/apps/parks/management/commands/create_sample_data.py

@@ -207,7 +207,7 @@ class Command(BaseCommand):
         self.stdout.write("Creating parks...")
 
         # Park creation data - will be used to create parks in the database
-        # TODO(THRILLWIKI-111): Complete park creation implementation
+        # See FUTURE_WORK.md - THRILLWIKI-111 for implementation plan
         parks_data = [
             {
                 "name": "Magic Kingdom",