Where can we find the official WWDC session / sample code for adopting the foldable iPhone (this generation's Duo hardware)?

We've been reverse-engineering behavior from the Simulator device profile alone. Is there a WWDC session, updated UIKit/SwiftUI documentation, or sample project specifically covering foldable iPhone adoption (window/scene handling, size-class behavior, collection/table view sizing, and the fold-posture API surface) that we should be building against instead of inferring behavior empirically?

Where can we find the official WWDC session / sample code for adopting the foldable iPhone (this generation's Duo hardware)?
 
 
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