feat(i18n): complete French locale and add common.changeLanguage

- Added `common.changeLanguage` key to `en.json`, `fr.json`, and `zh.json`.
- Updated `LanguageSelector.jsx` to use the new shared key.
- Completed `fr.json` with all keys from `en.json` and `zh.json`.
- Added translations for `closeSidebar`, `pricing`, and `language`.

web/src/i18n/locales/fr.json

@@ -2126,5 +2126,12 @@
   "域名黑名单": "Liste noire de domaines",
   "白名单": "Liste blanche",
   "黑名单": "Liste noire",
-  "切换语言": "Changer de langue"
+  "切换语言": "Changer de langue",
+  "common.changeLanguage": "Changer de langue",
+  "closeSidebar": "Fermer la barre latérale",
+  "pricing": "Tarification",
+  "language": "Langue",
+  "关闭侧边栏": "Fermer la barre latérale",
+  "定价": "Tarification",
+  "语言": "Langue"
 }