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.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 23852c00-4779-460a-9e0c-d09fee4b6c92
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Event-Id: f585829f-898b-492f-82a5-11f4a76c87fb
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/f209e72a-0939-48fa-84fc-57854de71967/23852c00-4779-460a-9e0c-d09fee4b6c92/ICRgny1
Replit-Helium-Checkpoint-Created: true

package-lock.json

@@ -42,6 +42,7 @@
         "@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",
@@ -3897,6 +3898,15 @@
       "integrity": "sha512-ScaPdn1dQczgbl0QFTeTOmVHFULt394XJgOQNoyVhZ6r2vLnMLJfBPd53SB52T/3G36VI1/g2MZaX0cwDuXsfw==",
       "license": "MIT"
     },
+    "node_modules/@types/web-push": {
+      "version": "3.6.4",
+      "resolved": "https://registry.npmjs.org/@types/web-push/-/web-push-3.6.4.tgz",
+      "integrity": "sha512-GnJmSr40H3RAnj0s34FNTcJi1hmWFV5KXugE0mYWnYhgTAHLJ/dJKAwDmvPJYMke0RplY2XE9LnM4hqSqKIjhQ==",
+      "license": "MIT",
+      "dependencies": {
+        "@types/node": "*"
+      }
+    },
     "node_modules/@types/ws": {
       "version": "8.5.13",
       "resolved": "https://registry.npmjs.org/@types/ws/-/ws-8.5.13.tgz",