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/config/initializers/sidekiq.rb

@@ -2,6 +2,10 @@ require "sidekiq/api"
 
 Sidekiq.configure_server do |config|
   config.redis = { url: ENV.fetch("REDIS_URL", "redis://localhost:6379/0") }
+
+  config.on(:startup) do
+    StreamPublisherSyncJob.ensure_chain
+  end
 end
 
 Sidekiq.configure_client do |config|