Add statistics page with metrics, charts, and insights functionality

- Implemented CSS styles for the statistics page layout and components.
- Developed JavaScript functionality for managing statistics, including data fetching, chart rendering, and tab navigation.
- Created HTML template for the statistics page, integrating dynamic content for metrics, charts, and insights.
- Added responsive design adjustments and loading states for better user experience.

static/js/managers/FilterManager.js

@@ -148,6 +148,8 @@ export class FilterManager {
             apiEndpoint = '/api/recipes/base-models';
         } else if (this.currentPage === 'checkpoints') {
             apiEndpoint = '/api/checkpoints/base-models';
+        } else {
+            return;
         }
         
         // Fetch base models