App: scelta canale YouTube MLTV/società, privacy e condivisione link.

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share_url unificato per Match Live TV e YouTube.

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

backend/app/models/stream_session.rb

@@ -90,6 +90,21 @@ class StreamSession < ApplicationRecord
     "#{MatchLiveTv.app_public_url.chomp('/')}/live/#{id}"
   end
 
+  def youtube_watch_url
+    return nil if youtube_broadcast_id.blank?
+    return nil if youtube_broadcast_id.to_s.start_with?("mock_")
+
+    "https://www.youtube.com/watch?v=#{youtube_broadcast_id}"
+  end
+
+  def share_url
+    if platform == "youtube"
+      youtube_watch_url.presence || watch_page_url
+    else
+      watch_page_url
+    end
+  end
+
   def terminal?
     status.in?(%w[ended error])
   end