Fix for NavigationPage.TitleView does not expand with host window in iPadOS 26+ (#33088)

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### Issue Description: 
On iPadOS 26+, NavigationPage.TitleView does not resize when the window
dimensions change during device rotation, causing the TitleView to
remain at its original width instead of expanding to fill the navigation
bar.

### Root Cause
iOS 26+ changed UIKit's layout behavior so that NavigationItem.TitleView
container frames are no longer automatically updated during
ViewWillTransitionToSize transitions, causing the TitleView to retain
its original dimensions even when the navigation bar resizes.

### Description of Change
Added explicit frame updates for the TitleView Container during view
controller transitions on iOS 26+ by leveraging
AnimateAlongsideTransition to synchronize the Container's frame with the
navigation bar's dimensions, ensuring smooth resizing during rotation
and window size changes.

### Issues Fixed
Fixes #[32722
](#32722)

### Tested the behaviour on the following platforms
- [ ] Android
- [ ] Windows
- [x] iOS
- [ ] Mac

### Note:
This PR extends the behavior introduced in #32815 by adding support for
the iPad scenario. As the earlier PR already provided the necessary test
coverage, no new testcases are included in this follow‑up.
 
### Output Screenshot
Before Issue Fix | After Issue Fix |
|----------|----------|
|<video width="300" height="150" alt="Before Fix"
src="https://github.com/user-attachments/assets/22f2318e-0cbf-40e4-bbe6-0fb89d22b49f">|<video
width="300" height="150" alt="After Fix"
src="https://github.com/user-attachments/assets/492bac5f-447a-4c1d-9262-e0877053c1f5">|

Author: SuthiYuvaraj

src/Controls/src/Core/Compatibility/Handlers/NavigationPage/iOS/NavigationRenderer.cs

@@ -1613,12 +1613,28 @@ UIImage GetEmptyBackIndicatorImage()
 				return empty;
 			}
 
+			/// <summary>
+			/// Called when the view controller's view transitions to a new size.
+			/// On iPad iOS 26+, manually updates TitleView frame to handle Stage Manager window resizing.
+			/// </summary>
 			public override void ViewWillTransitionToSize(SizeF toSize, IUIViewControllerTransitionCoordinator coordinator)
 			{
 				base.ViewWillTransitionToSize(toSize, coordinator);
 
 				if (UIDevice.CurrentDevice.UserInterfaceIdiom == UIUserInterfaceIdiom.Pad)
+				{
 					UpdateLeftBarButtonItem();
+
+					// For iOS 26+, force TitleView to re-layout on window size changes (iPad Stage Manager, multitasking)
+					// Complements TraitCollectionDidChange handling (device rotation) added in #32815
+					if (OperatingSystem.IsIOSVersionAtLeast(26) || OperatingSystem.IsMacCatalystVersionAtLeast(26))
+					{
+						coordinator.AnimateAlongsideTransition(_ =>
+						{
+							UpdateTitleViewFrameForOrientation();
+						}, null);
+					}
+				}
 			}
 
 			public override void TraitCollectionDidChange(UITraitCollection previousTraitCollection)