chore: Disable copilot usage after the response count is over (#11845)

Disable copilot if the response usage is over.

spec/enterprise/controllers/api/v1/accounts/captain/copilot_threads_controller_spec.rb

@@ -86,7 +86,28 @@ RSpec.describe 'Api::V1::Accounts::Captain::CopilotThreads', type: :request do
       end
 
       context 'with valid params' do
+        it 'returns error when usage limit is exceeded' do
+          account.limits = { captain_responses: 2 }
+          account.custom_attributes = { captain_responses_usage: 2 }
+          account.save!
+
+          post "/api/v1/accounts/#{account.id}/captain/copilot_threads",
+               params: valid_params,
+               headers: agent.create_new_auth_token,
+               as: :json
+
+          expect(response).to have_http_status(:success)
+
+          expect(CopilotMessage.last.message['content']).to eq(
+            'You are out of Copilot credits. You can buy more credits from the billing section.'
+          )
+        end
+
         it 'creates a new copilot thread with initial message' do
+          account.limits = { captain_responses: 2 }
+          account.custom_attributes = { captain_responses_usage: 0 }
+          account.save!
+
           expect do
             post "/api/v1/accounts/#{account.id}/captain/copilot_threads",
                  params: valid_params,
@@ -103,8 +124,15 @@ RSpec.describe 'Api::V1::Accounts::Captain::CopilotThreads', type: :request do
           expect(thread.assistant_id).to eq(assistant.id)
 
           message = thread.copilot_messages.last
-          expect(message.message_type).to eq('user')
           expect(message.message).to eq({ 'content' => valid_params[:message] })
+
+          expect(Captain::Copilot::ResponseJob).to have_been_enqueued.with(
+            assistant: assistant,
+            conversation_id: valid_params[:conversation_id],
+            user_id: agent.id,
+            copilot_thread_id: thread.id,
+            message: valid_params[:message]
+          )
         end
       end
     end