fix blank response validation

enterprise/app/helpers/captain/chat_response_helper.rb

@@ -19,7 +19,7 @@ module Captain::ChatResponseHelper
     JSON.parse(content)
   rescue JSON::ParserError => e
     Rails.logger.error "#{self.class.name} Assistant: #{@assistant.id}, Error parsing JSON response: #{e.message}"
-    { 'content' => content }
+    { 'response' => content, 'content' => content }
   end
 
   def apply_credit_usage_metadata(parsed_response)

enterprise/app/jobs/captain/conversation/response_builder_job.rb

@@ -80,7 +80,7 @@ class Captain::Conversation::ResponseBuilderJob < ApplicationJob
   end
 
   def handoff_requested?
-    @response['response'] == 'conversation_handoff'
+    @response['response'].blank? || @response['response'] == 'conversation_handoff'
   end
 
   def process_action(action)
@@ -109,14 +109,9 @@ class Captain::Conversation::ResponseBuilderJob < ApplicationJob
   end
 
   def create_messages
-    validate_message_content!(@response['response'])
     create_outgoing_message(@response['response'], agent_name: @response['agent_name'])
   end
 
-  def validate_message_content!(content)
-    raise ArgumentError, 'Message content cannot be blank' if content.blank?
-  end
-
   def create_outgoing_message(message_content, agent_name: nil)
     additional_attrs = {}
     additional_attrs[:agent_name] = agent_name if agent_name.present?