fix: package.json & package-lock.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-NEXT-15104645
- https://snyk.io/vuln/SNYK-JS-NEXT-15105315

Author: snyk-bot

package-lock.json

@@ -91,7 +91,7 @@
     "lowlight": "^3.1.0",
     "lucide-react": "^0.451.0",
     "nanoid": "^5.0.9",
-    "next": "^16.1.1",
+    "next": "^16.1.5",
     "next-auth": "^5.0.0-beta.30",
     "next-safe-action": "^7.9.4",
     "next-themes": "^0.4.6",