Add N8n integration with models, services, and routes

- Introduced N8n and N8nSetting models in both MySQL and PostgreSQL schemas.
- Implemented N8nController and N8nService for managing N8n bots.
- Created N8nRouter for handling API requests related to N8n.
- Added DTOs and validation schemas for N8n integration.
- Updated server module and chatbot controller to include N8n functionality.
- Configured environment settings for N8n integration.

src/api/integrations/chatbot/chatbot.controller.ts

@@ -4,6 +4,7 @@ import {
   difyController,
   evolutionBotController,
   flowiseController,
+  n8nController,
   openaiController,
   typebotController,
 } from '@api/server.module';
@@ -97,6 +98,8 @@ export class ChatbotController {
 
     await difyController.emit(emitData);
 
+    await n8nController.emit(emitData);
+
     await flowiseController.emit(emitData);
   }