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/youtube/broadcast_service.rb

@@ -47,14 +47,16 @@ module Youtube
         rtmp_url: stream_result.cdn.ingestion_info.ingestion_address
       }
     rescue Google::Apis::Error => e
+      ApiThrottle.mark_rate_limited! if ApiThrottle.rate_limit_error?(e.message)
       raise Error, friendly_api_error(e)
     end
 
     # Porta in onda appena c’è ingest su YouTube (non attendere scheduledStartTime).
-    # @return [Symbol] :live, :waiting_ingest, :transitioned, :skipped
+    # @return [Symbol] :live, :waiting_ingest, :transitioned, :skipped, :rate_limited
     def activate_broadcast!(broadcast_id)
       return :skipped if broadcast_id.blank?
       return :skipped if @credential.blank? || missing_oauth_config?
+      return :rate_limited if ApiThrottle.rate_limited?
 
       client = authorized_client
       item = client.list_live_broadcasts("status,contentDetails", id: broadcast_id).items&.first
@@ -68,7 +70,11 @@ module Youtube
       if stream_id.present?
         stream = client.list_live_streams("status", id: stream_id).items&.first
         stream_status = stream&.status&.stream_status.to_s
+        Rails.logger.info("[Youtube::BroadcastService] activate #{broadcast_id}: lifecycle=#{status} stream_status=#{stream_status.presence || "(blank)"}")
         return :waiting_ingest unless stream_status == "active"
+      else
+        Rails.logger.info("[Youtube::BroadcastService] activate #{broadcast_id}: lifecycle=#{status} stream_status=(unbound)")
+        return :waiting_ingest
       end
 
       if %w[ready created].include?(status)
@@ -82,6 +88,11 @@ module Youtube
 
       :skipped
     rescue Google::Apis::Error => e
+      if ApiThrottle.rate_limit_error?(e.message)
+        ApiThrottle.mark_rate_limited!
+        Rails.logger.warn("[Youtube::BroadcastService] activate rate limited #{broadcast_id}")
+        return :rate_limited
+      end
       Rails.logger.warn("[Youtube::BroadcastService] activate #{broadcast_id}: #{e.message}")
       :skipped
     end
@@ -133,6 +144,8 @@ module Youtube
         return "Orario programmazione YouTube non valido. Riprova: la diretta partirà appena invii il segnale RTMP."
       end
 
+      return "YouTube temporaneamente occupato. Riprova tra 1–2 minuti." if ApiThrottle.rate_limit_error?(msg)
+
       msg
     end