Security update: Patch React and Next.js CVE vulnerabilities

Updated React to 19.2.1 and Next.js to 16.0.7 to address critical security vulnerabilities:
- CVE-2025-55182: React Server Components deserialization flaw
- CVE-2025-66478: Next.js RSC implementation vulnerability

Also includes:
- Add PATCH endpoint for geofence updates
- Reorder admin navigation items
- Add geofence update functionality in database layer

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

package.json

@@ -36,11 +36,11 @@
     "better-sqlite3": "^12.4.1",
     "leaflet": "^1.9.4",
     "mqtt": "^5.14.1",
-    "next": "^16.0.3",
+    "next": "^16.0.7",
     "next-auth": "^5.0.0-beta.30",
     "nodemailer": "^7.0.10",
-    "react": "^19.2.0",
-    "react-dom": "^19.2.0",
+    "react": "^19.2.1",
+    "react-dom": "^19.2.1",
     "react-email": "^4.3.2",
     "react-leaflet": "^5.0.0",
     "typescript": "^5.9.3",