Aggiunge copertina sponsor custom solo Premium Full, con override in wizard e slate sui nodi di streaming.

Permette upload da portale e app con ereditarietà partita→squadra→società, generazione MP4 via ffmpeg e distribuzione su home lab e nodi CPX per pause e assenza segnale.

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

backend/app/controllers/concerns/branding_attachments.rb

@@ -8,6 +8,26 @@ module BrandingAttachments
     record.logo_file.attach(file) if file.present?
   end
 
+  def attach_cover_image(record, entitlements:)
+    remove_flag = params[:remove_cover].to_s == "1" || params.dig(:match, :remove_cover).to_s == "1"
+    if remove_flag
+      record.cover_image.purge if record.cover_image.attached?
+      record.cover_slate.purge if record.cover_slate.attached?
+      return
+    end
+
+    file = params.dig(:branding, :cover_image) || params[:cover_image]
+    return if file.blank?
+
+    entitlements.assert_can_upload_cover!
+    record.cover_slate.purge if record.cover_slate.attached?
+    record.cover_image.attach(file)
+  end
+
+  def enqueue_cover_slate_generation(record)
+    GenerateCoverSlateJob.enqueue_for(record) if record.cover_image.attached?
+  end
+
   def normalize_hex_color(value, fallback)
     v = value.to_s.strip
     v = "##{v}" if v.match?(/\A[0-9A-Fa-f]{6}\z/)