chore(deps): update dependency unhead to v3

Author: renovate[bot]

examples/vue-router/package.json

@@ -14,7 +14,7 @@
     "@vitejs/plugin-vue": "^6.0.3",
     "sirv-cli": "^3.0.1",
     "srvx": "^0.10.0",
-    "unhead": "^2.1.1",
+    "unhead": "^3.1.0",
     "vite": "^7.3.1",
     "vite-plugin-devtools-json": "^1.0.0",
     "vue": "^3.5.26",