[BUG] CloseOnBackground not honored on iOS

Description

Title: IDialogService popup with CloseOnBackgroundTapped="True" does not dismiss on iOS (Mopups container missing the dismiss mask)

This is the iOS counterpart to #3322 ("CloseOnBackgroundTapped not honored"), which was closed as fixed on the private feed. On Prism.Plugin.Popups.Maui 9.1.33-pre the flag is now plumbed correctly, but the popup still does not dismiss on background tap on iOS. I traced it to the container layout.

Environment

• Prism.DryIoc.Maui 9.1.111-pre, Prism.Maui 9.1.86-pre
• Prism.Plugin.Popups.Maui 9.1.33-pre, Mopups 1.3.4
• .NET 10, net10.0-ios, iOS 26 simulator + device

Root cause

The flag is read and applied — Prism.Maui's DialogServiceBase reads DialogLayout.GetCloseOnBackgroundTapped(view) and passes it to PopupDialogContainer.ConfigureLayout, which sets ((PopupPage)this).CloseWhenBackgroundIsClicked = hideOnBackgroundTapped.

The problem is the layout. PopupDialogContainer.GetContentLayout builds a screen-filling AbsoluteLayout with the dialog as a centered child, then leans on Mopups' CloseWhenBackgroundIsClicked to detect a background tap. But that mechanism only fires for a tap outside the content frame — and the AbsoluteLayout fills the whole page, so on iOS every tap is "inside content" and the background tap is never recognized.

By contrast, Prism.Maui's default container DialogContainerPage does not rely on Mopups detection — it adds a BoxView mask with a TapGestureRecognizer bound to the dismiss command. PopupDialogContainer is simply missing that mask.

Suggested fix

Give PopupDialogContainer the same mask + gesture that DialogContainerPage already uses, instead of depending on CloseWhenBackgroundIsClicked. A minimal override that does exactly this (drop-in proof, in the repro):

protected override View GetContentLayout(Page currentPage, View dialogView,
    bool hideOnBackgroundTapped, ICommand dismissCommand, IDialogParameters parameters)
{
    var content = base.GetContentLayout(currentPage, dialogView, hideOnBackgroundTapped,
        dismissCommand, parameters);

    if (hideOnBackgroundTapped && content is AbsoluteLayout layout)
    {
        var scrim = new BoxView { Color = Colors.Transparent };
        AbsoluteLayout.SetLayoutFlags(scrim, AbsoluteLayoutFlags.All);
        AbsoluteLayout.SetLayoutBounds(scrim, new Rect(0, 0, 1, 1));
        scrim.GestureRecognizers.Add(new TapGestureRecognizer { Command = dismissCommand });
        layout.Children.Insert(0, scrim); // behind the dialog
    }

    return content;
}

Steps to Reproduce

Repro

Minimal repo: [prism-popup-dismiss-repro]

1. UsePrism(... .ConfigureMopupDialogs() ...), register a dialog whose root sets prism:DialogLayout.CloseOnBackgroundTapped="True".
2. IDialogService.ShowDialog(...) it on iOS.
3. Tap the dimmed background.

Expected: dialog dismisses. Actual: dialog stays open.

Platform with bug

.NET MAUI

Affected platforms

iOS

Did you find any workaround?

No response

Relevant log output