Fix issues in windows-app-sdk/index.md

Update broken Windowing link from windowing/windowing-overview.md to the
current file location at ../develop/ui/windowing-overview.md. The old path
no longer exists in the repo; it was moved and a redirect (with
redirect_document_id: false) was added but that does not resolve for
doc-to-doc link validation.

Co-authored-by: Copilot <[email protected]>

Author: GrantMeStrength

hub/apps/windows-app-sdk/index.md

@@ -36,7 +36,7 @@ Here's a breakdown of the major features that Windows App SDK provides:
 | [Modern text rendering](dwritecore.md) | Use a device-independent text layout and rendering system with [ClearType](/typography/cleartype/) subpixel rendering, hardware acceleration, and broad language support for precise, high-quality text. |
 | [Resource management](mrtcore/mrtcore-overview.md) | Manage app resources such as strings and images in multiple languages, scales, and contrast variants independently of your app's logic. |
 | [App lifecycle](applifecycle/applifecycle.md) | Manage key aspects of your app's runtime behavior, including [instance management](applifecycle/applifecycle-instancing.md), [rich activation](applifecycle/applifecycle-rich-activation.md) (file, protocol, restart, and more), and [power management](applifecycle/applifecycle-power.md). Gain control over how your app starts, runs, and conserves system resources. |
-| [Windowing](windowing/windowing-overview.md) | Create, position, and customize app windows with modern windowing APIs. |
+| [Windowing](../develop/ui/windowing-overview.md) | Create, position, and customize app windows with modern windowing APIs. |
 | Notifications | Send local or cloud-based notifications to engage users and keep your app connected, including both [app notifications](../develop/notifications/app-notifications/index.md) and [push notifications](../develop/notifications/push-notifications/index.md). |
 | [Widgets](../develop/widgets/widget-providers.md) | Bring personalized, glanceable information to the Windows widget board, allowing users to stay connected to your app's live content right from their desktop. |
 | [XAML Islands](../desktop/modernize/xaml-islands/xaml-islands.md) | Embed modern Windows UI controls inside existing desktop apps to refresh your interface and add new capabilities without a full rewrite. |