fix(iOS, Tabs): Request layout pass after loading image from source

[t0maboro]

Description

Before assigning the image, the tab bar might already be attached to the view hierarchy. This can cause an issue where the tab bar layout is not correctly updated, as it might have been added to the window before the image was set. As a result, the layout adjustments (e.g., image positioning) are not applied immediately.

To resolve this, we explicitly request an additional layout pass after the image is assigned. This ensures that the tab bar updates its layout properly without requiring user interaction (e.g., switching tabs) to trigger a recalculation.

The issue is illustrated in the image below.

Changes

• Add layout request in the completion callback when the image is loaded from source.
• Add example & assets demonstrating the issue.

Before & after - visual documentation

Before	After
before.mov	after.mov

Test plan

Added Test3596, performed regression testing on TestBottomTabs

Checklist

• Included code example that can be used to test this change.
• Updated / created local changelog entries in relevant test files.
• For visual changes, included screenshots / GIFs / recordings documenting the change.
• For API changes, updated relevant public types.
• Ensured that CI passes