Fix display of the artifact created by a tool

A tool ("get_incident_data) which has the following code

```
await tool_context.save_artifact("incident_data",
Part(inline_data=Blob(
display_name=f"Full data for incident {incident_id}",
mime_type="text/json",
data=full_data.model_dump_json().encode(
"utf-8"))))

```

displays the following widget in the UI:

The button name is not the actual artifact name/description. Clicking on the button results in a pop-up stating "Could not open the data. It might be invalid or too large. Check the browser console for errors.". The actual data in this case is very small.