Download clients now use thingy provider
Validation, settings UI cleanup and different settings models, oh my

New: Download client UI matches other settings
Fixed: Prevent drone factory folder from being set to invalid paths/root path for series
Fixed: Switching pages in settings will not hide changes
Fixed: Test download clients
Fixed: Settings are validated before saving
Fixed root folder integration test
Reordered migrations after rebase
Fixed a copy pasta error for SAB history