Add Blob's "display_name" to the Artifacts tab view

[slilichenko]

Currently, display name is not used, but it can be useful to provide in the UI. For example, this 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"))))

gets rendered as shown on this image: