fix MR comments

app/models/music_release.rb

@@ -8,7 +8,13 @@ class MusicRelease < ApplicationRecord
   include Taggable
   include PersonName
   include CsvExportable
-  
+
+  class << self
+    def custom_csv_exportable_headers
+      %i[name file_infos_count composers_count publishers_count]
+    end
+  end
+
   has_many :file_infos, as: :releasable, dependent: :destroy
   has_many :composers, dependent: :destroy
   has_many :publishers, dependent: :destroy
@@ -73,6 +79,18 @@ class MusicRelease < ApplicationRecord
     false
   end
 
+  def file_infos_count
+    file_infos.size
+  end
+
+  def composers_count
+    composers.size
+  end
+
+  def publishers_count
+    publishers.size
+  end
+
   private
 
   def publisher_percentages_add_up_to_100