Fixes a regression where Timelapse and SD Card media failed to load on Bambu devices.
During the dual-cloud-agent refactor, NetworkAgent was updated to require an explicit provider argument. The call site in MediaFilePanel::fetchUrl() was missing this argument, causing it to silently fall back to the default Orca stub instead of routing to the Bambu network plugin.
This explicitly passes wxGetApp().get_printer_cloud_provider() to get_camera_url to correctly route the request and restore functionality.
