chore(deps): update dependency @vitejs/plugin-legacy to v8 (#5830)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

frontend/package.json

@@ -54,7 +54,7 @@
     "@types/lodash-es": "^4.17.12",
     "@types/node": "^24.10.1",
     "@typescript-eslint/eslint-plugin": "^8.37.0",
-    "@vitejs/plugin-legacy": "^7.2.1",
+    "@vitejs/plugin-legacy": "^8.0.0",
     "@vitejs/plugin-vue": "^6.0.1",
     "@vue/eslint-config-prettier": "^10.2.0",
     "@vue/eslint-config-typescript": "^14.6.0",