Apple Watch: app is not downloading over WiFi

### Issue

A user is unable to get the Watch app to download over wifi when iPhone is in airplane mode. They have the most recent iOS and Watch versions (iPhone 12 and Apple Watch 6). They have tried signing out of the phone app, then back in, restarting the Watch, and left charging > 20 minutes.

Some additional information from this user:

>I have a new watch now, still doesn’t work.
>
> I am trying to use W as play source (I use this while running and not carrying a phone.).
>
> The phone is in airplane mode when I try direct download to watch.
>
> Podcasts will load to watch when phone is on, albeit quite slowly. I presume that is through Bluetooth.
>
> This is a feature that used to work and that I used regularly. I find it’s disappearance frustrating.

The issue identifies an Apple Watch download failure when the iPhone is in airplane mode, but it names no files, tests, or entry points. Start by reproducing the reported WiFi and Bluetooth behavior with an iPhone 12 and Apple Watch 6; done means downloads work directly to the Watch while the phone is offline.

Written by the indexing model from the issue text.