Do not inform user about message_draft diff in validations

app/jobs/fs/validate_message_draft_result_job.rb

@@ -14,11 +14,21 @@ def perform(message_draft, location_header, fs_client: FsEnvironment.fs_client)
       message_draft.metadata[:validation_errors] = {
         result: response[:body]['result'],
         errors: response[:body]['problems']&.select { |problem| problem['level'] == 'error' }&.map{ |problem| problem['message'] },
-        warnings: response[:body]['problems']&.select { |problem| problem['level'] == 'warning' }&.map{ |problem| problem['message'] }
+        warnings: response[:body]['problems']&.select { |problem| problem['level'] == 'warning' }&.map{ |problem| problem['message'] },
       }
-      message_draft.add_cascading_tag(message_draft.tenant.submission_error_tag)
+
+      diff = response[:body]['problems']&.select { |problem| problem['level'] == 'diff' }
+      log("Message draft DIFF: #{diff.map{ |problem| problem['message']}.join(', ')}") if diff.any?
+
+      message_draft.add_cascading_tag(message_draft.tenant.submission_error_tag) if message_draft.metadata[:validation_errors][:errors].any? || message_draft.metadata[:validation_errors][:warnings].any?
     end
 
     message_draft.save
   end
+
+  private
+
+  def log(message)
+    Rails.logger.info(message)
+  end
 end