additional the README.md

Author: dotpep

README.md

@@ -20,6 +20,8 @@ The Architecture AI Assistant enables users to:
 - **Storage**: DynamoDB for session-based chat history, S3 for diagram files
 - **Infrastructure**: Terraform for Infrastructure-as-Code
 
+![High Level Architecture](/docs/architecutre-diagram.png)
+
 ### Session Management
 
 The application uses a session-based architecture where: