fix(security): keep fallback templates running when captain feature is revoked

enterprise/app/services/enterprise/message_templates/hook_execution_service.rb

@@ -82,7 +82,9 @@ module Enterprise::MessageTemplates::HookExecutionService
     ::MessageTemplates::Template::OutOfOffice.perform_if_applicable(conversation)
   end
 
+  # Only let Captain suppress the fallback templates when it can actually reply; otherwise a revoked
+  # feature would leave the contact with neither a Captain response nor a greeting/OOO/email-collect.
   def captain_handling_conversation?
-    conversation.pending? && inbox.respond_to?(:captain_assistant) && inbox.captain_assistant.present?
+    conversation.pending? && inbox.respond_to?(:captain_assistant) && inbox.captain_assistant.present? && captain_feature_enabled?
   end
 end

spec/enterprise/services/enterprise/message_templates/hook_execution_service_spec.rb

@@ -203,6 +203,29 @@ RSpec.describe MessageTemplates::HookExecutionService do
     end
   end
 
+  context 'when the Captain feature is disabled but an assistant is still linked' do
+    before do
+      account.disable_features!('captain_integration', 'captain_integration_v2')
+      conversation.update!(status: :pending)
+    end
+
+    it 'does not schedule captain response job' do
+      expect(Captain::Conversation::ResponseBuilderJob).not_to receive(:perform_later)
+
+      create(:message, conversation: conversation, message_type: :incoming, account: account)
+    end
+
+    it 'falls back to the greeting message instead of leaving the contact without a reply' do
+      inbox.update!(greeting_enabled: true, greeting_message: 'Hello! How can we help you?', enable_email_collect: false)
+
+      expect do
+        create(:message, conversation: conversation, message_type: :incoming, account: account)
+      end.to change { conversation.reload.messages.template.count }.by(1)
+
+      expect(conversation.reload.messages.template.last.content).to eq('Hello! How can we help you?')
+    end
+  end
+
   context 'when Captain is not configured' do
     before do
       CaptainInbox.where(inbox: inbox).destroy_all