cursor appearance blinking ibeam<->arrow in TextBox while clicking

### Describe the bug

Hello,

while clicking in a TextBox (not read-only), the appearance of the cursor switches from ibeam to arrow appearance on mouse up which is incorrect: especially if you click and just after move mouse in a TextBox the appearance is blinking rapidly ibeam->arrow->ibeam which is very annoying.

Best regards

### Why is this important?

This issue is very annoying for end user experience with TextBox: cursor appearance should not blink while clicking in editable area.

### Steps to reproduce the bug

Open WINUI3 Gallery
choose TextBox sample (not read-only)
click in it (in the editable area while cursor appearance is ibeam so): cursor appearance swiches to arrow (wrong)
click and move mouse just after -> cursor appearance blinks ibeam->arrow->ibeam (wrong)

### Actual behavior

cursor appearance is switching from ibeam to arrow while clicking in a textBox which is wrong (and back to ibeam if mouse is moved after clicking)

### Expected behavior

cursor appearance should not change (to arrow) while clicking in a textBox: cursor appearance should remain ibeam.

### Screenshots

_No response_

### NuGet package version

Microsoft.WindowsAppSDK.WinUI 2.0.12

### Windows version

Windows 11 (24H2): Build 26100

### Additional context

This issue is easely reproducible with latest WINUI3 Gallery app official release in Microsoft Store (which uses Windows App SDK 2.2 at current date) in a TextBox so.
Also we reproduce in our own app using WindowsAppSDK 2.0, but not with WindowsAppSDK 1.8 so probably a regression since WindowsAppSDK 2.0 release ?

Reproduce the issue in the WinUI 3 Gallery TextBox sample using the reported Windows App SDK versions, then compare the behavior between 1.8 and 2.0. Trace the TextBox pointer and cursor handling to identify the regression; done means the editable TextBox keeps the ibeam cursor while clicking and moving the mouse.

Written by the indexing model from the issue text.