Beta: dock devices on front USB-C ports now show up

Another beta for testers ahead of 1.2.0. Nothing about your Pro licence or
how the app works changes. Same as before, please flag anything that looks
off.

What to test

• Devices behind a dock on a desktop's front USB-C port now appear. On a
  Mac mini or Studio, plugging a dock into a front port used to show the
  dock's own hubs but drop everything plugged into the dock (drives, phones,
  audio). Those devices now show under "Built-in USB ports", nested under the
  dock. Devices on the rear Thunderbolt ports were never affected. Thanks
  @jimmyorz for the report and the detailed testing (#430).

Also in this build

• Cable database updates: several newly reported cables added, and a
  Thunderbolt adapter relabelled.