"Download" button in missing models panel uses browser download instead of server-side download to configured paths

When a workflow has missing models, the \"Download\" button in the Workflow Overview errors panel triggers a browser download (saving to the OS downloads folder) instead of a server-side download to the paths configured in `extra_model_paths.yaml`.

## Expected behavior
Clicking \"Download\" should have the ComfyUI server fetch the file and save it directly to the correct configured model folder (e.g. `diffusion_models/`, `loras/`) on the server, respecting `extra_model_paths.yaml` and `is_default: true`.

## Actual behavior
The browser downloads the file to the user's default downloads folder, ignoring any server-side path configuration. Users on remote setups (NAS, network storage, headless servers) are forced to manually move files after downloading.

## Workaround
Use \"Copy URL\" and run `wget -P ` in a terminal.