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.

controllers/_renderSingletonPageView.js

@@ -0,0 +1,31 @@
+function createRenderSingletonPageView({
+  model,
+  editorConfig,
+  view,
+  normalizeForEditor,
+}) {
+  return async function renderSingletonPageView(req, res) {
+    const doc = await model.getSingle();
+    const rawData = doc.toObject();
+    const data = normalizeForEditor ? normalizeForEditor(rawData, req) : rawData;
+    const frontendUrl = process.env.FRONTEND_URL || "http://localhost:3000";
+    const backendUrl =
+      process.env.BACKEND_URL ?? `${req.protocol}://${req.get("host")}`;
+
+    return res.render(view, {
+      layout: "layouts/main",
+      title: editorConfig.title,
+      subtitle: editorConfig.subtitle,
+      data,
+      editorConfig,
+      activeTab: req.query.tab || editorConfig.tabs[0].key,
+      frontendUrl,
+      backendUrl,
+      previewUrl: `${frontendUrl}${editorConfig.previewPath}`,
+      currentPath: req.path,
+      user: req.session.user,
+    });
+  };
+}
+
+module.exports = createRenderSingletonPageView;