adding poi for new multilingual support & add news for the new feature

lib/api/routes/userSettingsRoute.js

@@ -179,6 +179,7 @@ export default async function userSettingsPlugin(fastify) {
 
     try {
       upsertSettings({ language }, userId);
+      await trackPoi(TRACKING_POIS.CHANGE_LANGUAGE);
       return { success: true };
     } catch (error) {
       logger.error('Error updating language setting', error);