chore(deps-dev): bump @vitest/coverage-v8 from 3.2.4 to 4.0.18 in /ui

Bumps [@vitest/coverage-v8](https://github.com/vitest-dev/vitest/tree/HEAD/packages/coverage-v8) from 3.2.4 to 4.0.18.
- [Release notes](https://github.com/vitest-dev/vitest/releases)
- [Commits](https://github.com/vitest-dev/vitest/commits/v4.0.18/packages/coverage-v8)

---
updated-dependencies:
- dependency-name: "@vitest/coverage-v8"
  dependency-version: 4.0.18
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

ui/package.json

@@ -51,7 +51,7 @@
     "@types/react": "^19",
     "@types/react-dom": "^19",
     "@vitejs/plugin-react": "^4.5.0",
-    "@vitest/coverage-v8": "^3.2.3",
+    "@vitest/coverage-v8": "^4.0.18",
     "eslint": "^9",
     "eslint-config-next": "16.1.1",
     "jsdom": "^26.1.0",