chore(deps-dev): Bump typescript in /build/frontend-legacy

Bumps [typescript](https://github.com/microsoft/TypeScript) from 5.9.3 to 6.0.3.
- [Release notes](https://github.com/microsoft/TypeScript/releases)
- [Commits](microsoft/TypeScript@v5.9.3...v6.0.3)

---
updated-dependencies:
- dependency-name: typescript
  dependency-version: 6.0.3
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

build/frontend-legacy/package-lock.json

@@ -125,7 +125,7 @@
     "raw-loader": "^4.0.2",
     "regextras": "^0.8.0",
     "sass": "^1.100.0",
-    "typescript": "^5.9.2",
+    "typescript": "^6.0.3",
     "vite": "^7.3.5",
     "vitest": "^4.1.4",
     "vue-loader": "^15.11.1",