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

Bumps [vitest](https://github.com/vitest-dev/vitest/tree/HEAD/packages/vitest) 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/vitest)

---
updated-dependencies:
- dependency-name: vitest
  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

@@ -58,6 +58,6 @@
     "jsdom": "^26.1.0",
     "tailwindcss": "^4",
     "typescript": "^5",
-    "vitest": "^3.2.3"
+    "vitest": "^4.0.18"
   }
 }