_WebKit_SwiftUI cross-import overlay

A cross-import overlay that bridges WebKit and SwiftUI, providing the WebView and WebPage types for embedding and controlling web content within SwiftUI apps. Use it to display and drive web content as part of a SwiftUI view hierarchy on iOS, macOS, and visionOS. The overlay declares no types of its own; it surfaces WebKit's web-rendering capabilities through SwiftUI's declarative model.