feat(cms): refactor page content management and implement detailed editors

Refactor the CMS page content system to use a more modular configuration-driven approach. This replaces the monolithic `pageContentConfig.js` with individual configuration files for each page and introduces a shared field utility to standardize editor components.
Key changes:
- Implement a generic `_renderSingletonPageView` helper to reduce duplication across controllers.
- Enhance `_createPageContentController` with `normalizeForEditor`, `normalizeForApi`, and `preparePayload` hooks for custom data transformation.
- Create dedicated configuration and view structures for Partnerships, History, Accreditation, Admissions, and Policies pages.
- Add a specialized section editor for Policies to manage complex nested content.
- Improve the frontend `page-content-editor.js` with support for visibility logic, auto-sequencing for arrays, and URL synchronization for active tabs.
- Update data JSON files to align with the new schema.

routes/admin.js

@@ -81,6 +81,16 @@ router.post(
 );
 router.get("/policies", ensureAuthenticated, policiesController.index);
 router.post("/policies/update", ensureAuthenticated, policiesController.update);
+router.get(
+  "/policies/:policyId/section",
+  ensureAuthenticated,
+  policiesController.editSections,
+);
+router.post(
+  "/policies/:policyId/section/update",
+  ensureAuthenticated,
+  policiesController.updateSections,
+);
 
 // Booking admin CRUD removed