chore(deps): update devdependency vitest to v4

Author: renovate[bot]

package.json

@@ -47,7 +47,7 @@
     "typescript": "5.9.3",
     "unbuild": "^3.6.1",
     "utility-types": "^3.11.0",
-    "vitest": "^3.2.4",
+    "vitest": "^4.0.0",
     "vitest-package-exports": "^0.1.1",
     "vue": "^3.5.22",
     "vue-tsc": "^3.0.9"