Update Vitest and its plugins to v4

Author: renovate[bot]

package.json

@@ -37,15 +37,15 @@
     "@types/chrome": "0.1.29",
     "@types/jest": "30.0.0",
     "@types/node": "24.10.1",
-    "@vitest/coverage-v8": "3.2.4",
+    "@vitest/coverage-v8": "4.0.13",
     "ncp": "2.0.0",
     "prettier": "3.6.2",
     "rimraf": "6.1.0",
     "rollup": "4.53.2",
     "tslib": "2.8.1",
     "typescript": "5.9.3",
     "typescript-eslint": "8.46.4",
-    "vitest": "3.2.4",
+    "vitest": "4.0.13",
     "web-ext": "9.1.0"
   }
 }