get https://sync-dev.bkbn.com/materials//
Requests materials (media files, documents, or result URLs) for a given order and assignment.
The response includes:
- Media files (photos, videos) when applicable for the product type
- Result URLs for virtual tours and similar products that don't have downloadable files
- Documents for document-based product types
The visualType parameter is optional and defaults to POST. For document products,
it should be set to DOCUMENT or omitted.