The Download button does not work in the deployment window

### Environment

Flowset Control 2026.0.0-rc (portable)

### Bug Description

<img width="1906" height="774" alt="Image" src="https://github.com/user-attachments/assets/d8e36284-488a-4d41-895c-5f2b385872b1" />

[my-camunda-demo-project.zip](https://github.com/user-attachments/files/25761188/my-camunda-demo-project.zip)

ER
If the file cannot be generated, show an error message