Remove background color for SwiftUI HostingVC

[thisIsTheFoxe]

Make sure hosting VC doesn't have a background color.
Still supports .background from the content view, but if no background is set, make sure it's transparent.
If the background is NOT set, the UIHostingController adds the default bg color for the current color scheme / appearance.

Example

struct ContentView: View {
    var body: some View {
        VStack {
            Image(systemName: "globe")
                .imageScale(.large)
                .foregroundStyle(.tint)
            Text("Hello, World!")
                .screenshotProtected(isProtected: true)
        }
        .padding()
        .background(Color.red)
    }
}