fix: align i18n namespace loading

frontend/src/i18n.ts

@@ -9,6 +9,9 @@ i18n
     .use(initReactI18next)
     .init({
         fallbackLng: 'en',
+        load: 'languageOnly',
+        ns: ['common'],
+        defaultNS: 'common',
         detection: {
             order: ['localStorage', 'navigator'],
             lookupLocalStorage: 'app_lang_',
@@ -18,4 +21,4 @@ i18n
             loadPath: '/locales/{{lng}}/{{ns}}.json',
         },
         interpolation: { escapeValue: false },
-    });
+    });