Refresh presigned URLs for a multipart storage upload

Returns fresh presigned upload URLs for specific parts of an in-progress multipart upload created by `/v2/storage/uploads`. Use this to resume an upload after part URLs expire instead of restarting the whole upload. Only uploads owned by the authenticated user can be refreshed.

curl -X POST "https://example.com/v2/storage/uploads/refresh" \  -H "Content-Type: application/json" \  -d '{    "file_path": "presigned_upload/user_123/source.mp4",    "upload_id": "2~example-upload-id",    "part_numbers": [      3,      7    ]  }'

{  "upload_urls": [    {      "part_number": 3,      "upload_url": "https://example-bucket.s3.amazonaws.com/presigned_upload/user_123/source.mp4?partNumber=3&X-Amz-Signature=..."    }  ],  "method": "PUT"}