Separate the concepts of archived and disconnected devices

Summary:
Minor code cleanup to avoid future confusion:

- archived: a device that was imported from a Flipper trace, and only has persisted state
- (dis)connected: a real stateful device that might or might not have an active connection

Reviewed By: nikoant

Differential Revision: D26275459

fbshipit-source-id: eba554b37c39711e367c3795ff4456329a303c22

desktop/app/src/dispatcher/iOSDevice.tsx

@@ -118,7 +118,7 @@ function processDevices(
         (device) =>
           device instanceof IOSDevice &&
           device.deviceType === type &&
-          !device.isArchived,
+          device.connected.get(),
       )
       .map((device) => device.serial),
   );