watchOS Background Tasks in a SwiftUI world

TL;DR where can I find a translation of this page for a SwiftUI App world?

Essentially I was looking to dip my toe in the SwiftUI water by reimplementing a super simple Watch app I wrote to get the battery status of my Nissan LEAF. It doesn't have to do much beyond waking up, querying a URL for some JSON and updating a complication. I failed at the first hurdle because I couldn't see where to handle the WKApplicationRefreshBackgroundTask without a WKExtensionDelegate. Any help, pointers to obvious-yet-somehow-missed documentation or WWDC videos welcomed.
Somebody just suggested I look at WKExtensionDelegateAdaptor so that may solve it. Still handle the tasks in an WKExtensionDelegate object but just connect that into the App
I couldn't get this to work by using App and WKExtensionDelegateAdaptor (see discussion here) with watchOS beta 3, but if you do, I'd like to hear how. I had to revert to using Interface.storyboard and a WKHostingController.

I'll have to recheck everything and try it out again some day soon. My use case is exactly as yours, downloading a simple JSON and then updating complications.
watchOS Background Tasks in a SwiftUI world
 
 
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