Update dependency vitest to v4

Author: dependencyupdates[bot]

src/Frontend/package.json

@@ -76,7 +76,7 @@
     "vite": "7.1.12",
     "vite-plugin-checker": "0.11.0",
     "vite-plugin-vue-devtools": "8.0.3",
-    "vitest": "3.2.4",
+    "vitest": "4.0.4",
     "vue-tsc": "3.1.2"
   },
   "msw": {