Update dependency nuxt to v4

Author: renovate[bot]

package.json

@@ -14,7 +14,7 @@
     "@oxc-parser/binding-linux-x64-gnu": "^0.99.0",
     "@playwright/test": "^1.57.0",
     "autoprefixer": "^10.4.22",
-    "nuxt": "^3.20.0",
+    "nuxt": "^4.2.1",
     "nuxt-icon": "^0.6.10",
     "prettier": "^3.7.3",
     "tailwindcss": "^3.4.18"