Add defaultWelcome lang string

server/config/bbb.js

@@ -43,7 +43,7 @@ export async function createMeeting(room, logoutURL, loginURL = null) {
   const { moderatorPW, attendeePW } = getRoomPasswords(room.uid);
 
   // Build welcome message with guest invite link
-  let welcome = room.welcome_message || 'Welcome to this meeting!';
+  let welcome = room.welcome_message || t('defaultWelcome');
   if (logoutURL) {
     const guestLink = `${logoutURL}/join/${room.uid}`;
     welcome += `<br><br>To invite other participants, share this link:<br><a href="${guestLink}">${guestLink}</a>`;