Files generated by created agents in Agents (BETA) are stored in File System and cannot be downloaded by clicking

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### Dify version

1.16.1

### Cloud or Self Hosted

Self Hosted (Docker)

### Steps to reproduce

1. Enter Agents (BETA) module
2. Create and run an agent task that outputs a file
3. The generated file appears in the File System list
4. Click on the file entry

### ✔️ Expected Behavior

File download should start after clicking the file item.

### ❌ Actual Behavior

The file entry is unclickable, no download action is triggered.

Reproduce the issue in the Agents (BETA) module by running an agent task that outputs a file, then inspect the frontend component that renders the File System list and its existing click or download handling. Done means clicking a generated file entry starts the file download instead of doing nothing.

Written by the indexing model from the issue text.