fix: examples/react-nextjs/package.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

examples/react-nextjs/package.json

@@ -15,7 +15,7 @@
     "@evolu/react-web": "latest",
     "@tabler/icons-react": "^3.35.0",
     "clsx": "^2.1.1",
-    "next": "^16.0.0",
+    "next": "^16.1.5",
     "react": "19.1.0",
     "react-dom": "19.1.0"
   },