When the window size changes, the pull-to-refresh control disappears while refreshing.

### Describe the bug

When the window size changes, the pull-to-refresh control disappears while refreshing.

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窗口大小发生变化时，正在刷新时的下拉刷新控件会消失

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### Why is this important?

See description

### Steps to reproduce the bug

1.Create PullToRefresh controls
2.Start to pull to refresh
3.Resize Window and see window state

### Actual behavior

When the window size changes, the pull-to-refresh control disappears while refreshing.

### Expected behavior

When the window size changes, the pull-to-refresh control does not disappears while refreshing.

### Screenshots

https://github.com/user-attachments/assets/db43854e-c063-4ef4-8941-96fcfdb809a5

### NuGet package version

All Windows App SDK and UWP version

### Windows version

Windows 11 (26H1): Build 28000

### Additional context

None

Start by reproducing the issue with a PullToRefresh control using the listed steps: begin a refresh, then resize the window. Trace the PullToRefresh implementation and its resize-related behavior; done means the control remains visible while refreshing after the window size changes on the reported Windows App SDK and UWP versions.

Written by the indexing model from the issue text.