Toast Messages Not Shown as Part of iOS + SwiftUI Replays

[jas-kas]

Description

Toast messages are a common pattern to show error messages to users as well as other key information. Today, they're not shown as part of the replay video for iOS+SwiftUI, which leads to no visual indication of errors in some cases. This makes debugging with replays more challenging.

[philprime]

To add more context:

There are multiple approaches to add toasts.
One approach is using overlays in the same UIWindow with a high z-position (closer to viewer than other screen content), which should be picked by the current implementation of session replay.

Another option is using multiple windows and stack them on top of each other. All of them will be rendered and displayed on screen depending on their coordinates. Session replay currently only renders the key window, therefore any overlays are not included.

This could also lead to issues with the wrong window being rendered.