List every file in a folder

List every file under one folder, at any depth, as a flat paginated list, to preview what importing that folder would bring in. Pass the browse_ref fields of a folder or container. Each file carries its path relative to that folder. A page returns as soon as it holds files, so it may be shorter than page_size while cursor is still set; keep requesting until cursor is null. The listing stops after 10,000 files and sets truncated. Returns 422 contents_not_supported when the provider cannot list folder contents, and shares the provider request budget with browsing and background runs.