YouTube come destinazione pubblica, non Match Live TV.

Non propone più il link MLTV per sessioni YouTube; la pagina /live
reindirizza a YouTube; il relay verso YouTube si riavvia al connect.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/models/stream_session.rb

@@ -119,11 +119,13 @@ class StreamSession < ApplicationRecord
   end
 
   def share_url
-    if platform == "youtube"
-      youtube_watch_url.presence || watch_page_url
-    else
-      watch_page_url
-    end
+    return youtube_watch_url if platform == "youtube"
+
+    watch_page_url
+  end
+
+  def youtube_ready?
+    platform == "youtube" && youtube_watch_url.present?
   end
 
   def link_only?