Stabilizza live YouTube/RTMP e fix crash rotazione mobile.

Pipeline YouTube con relay, overlay e publisher sync lato backend; fix GL pauseGlDuringRotation su Android per evitare crash in rotazione durante lo streaming Flutter.

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

backend/app/services/webhooks/mediamtx_handler.rb

@@ -25,8 +25,10 @@ module Webhooks
     def handle_connect(session)
       return if session.paused?
 
-      Streams::OverlayRelay.ensure_publishing!(session)
-      Streams::YoutubeRelay.ensure_publishing!(session) if session.platform == "youtube"
+      if Mediamtx::PublisherOnline.active?(session) && session.platform == "youtube"
+        Mediamtx::PublisherSync.schedule_youtube_pipeline!(session)
+      end
+      Streams::YoutubeRelay.stop(session) if session.platform == "youtube"
 
       return if session.live? && session.stream_events.where(event_type: "connected").exists?
 
@@ -112,7 +114,6 @@ module Webhooks
 
     def broadcast(session, event)
       SessionChannel.broadcast_message(session, { type: "stream_event", event: event })
-      Streams::Overlay::Refresh.call(session)
     end
   end
 end