chore(deps): bump i18next from 25.8.18 to 25.8.20 in /frontend

Bumps [i18next](https://github.com/i18next/i18next) from 25.8.18 to 25.8.20.
- [Release notes](https://github.com/i18next/i18next/releases)
- [Changelog](https://github.com/i18next/i18next/blob/master/CHANGELOG.md)
- [Commits](i18next/i18next@v25.8.18...v25.8.20)

---
updated-dependencies:
- dependency-name: i18next
  dependency-version: 25.8.20
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

frontend/package.json

@@ -9,7 +9,7 @@
     "preview": "vite preview"
   },
   "dependencies": {
-    "i18next": "^25.8.18",
+    "i18next": "^25.8.20",
     "i18next-browser-languagedetector": "^8.2.1",
     "lucide-react": "^0.577.0",
     "react": "19.2.4",