Add web push notification system for user engagement and updates

Implement a web push notification system, including service worker integration, user subscription management, and an admin interface for sending broadcast messages.

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package.json

@@ -44,6 +44,7 @@
     "@tanstack/react-query": "^5.60.5",
     "@types/dompurify": "^3.0.5",
     "@types/multer": "^2.0.0",
+    "@types/web-push": "^3.6.4",
     "class-variance-authority": "^0.7.1",
     "cloudinary": "^2.9.0",
     "clsx": "^2.1.1",