feat: Update UI for Copilot (#11561)

- Updated UI for copilot

enterprise/app/controllers/enterprise/api/v1/accounts/conversations_controller.rb

@@ -1,31 +1,5 @@
 module Enterprise::Api::V1::Accounts::ConversationsController
   extend ActiveSupport::Concern
-  included do
-    before_action :set_assistant, only: [:copilot]
-  end
-
-  def copilot
-    # First try to get the user's preferred assistant from UI settings or from the request
-    assistant_id = copilot_params[:assistant_id] || current_user.ui_settings&.dig('preferred_captain_assistant_id')
-
-    # Find the assistant either by ID or from inbox
-    assistant = if assistant_id.present?
-                  Captain::Assistant.find_by(id: assistant_id, account_id: Current.account.id)
-                else
-                  @conversation.inbox.captain_assistant
-                end
-
-    return render json: { message: I18n.t('captain.copilot_error') } unless assistant
-
-    response = Captain::Copilot::ChatService.new(
-      assistant,
-      previous_history: copilot_params[:previous_history],
-      conversation_id: @conversation.display_id,
-      user_id: Current.user.id
-    ).generate_response(copilot_params[:message])
-
-    render json: { message: response['response'] }
-  end
 
   def inbox_assistant
     assistant = @conversation.inbox.captain_assistant