ColorPicker poor performance

### Describe the bug

The performance is especially bad when dragging the cursor rapidly in a circle. The tooltip never updates and the color stucks.

### Why is this important?

This is affecting both UWP and WinUI3. And for UWP, it is affecting even system settings.

### Steps to reproduce the bug

1. Go to winui 3 gallery, ColorPicker page
2. Drag around the color

### Actual behavior

Sluggish

### Expected behavior

Responsive.

### Screenshots

UWP:

winui3:

### NuGet package version

2.2

### Windows version

Windows 11 (26H1): Build 28000

### Additional context

The issue has been raised before in #2683, and we got an answer saying:

> I think we just have to wait for computers running WinUI to get faster :)

I am using 9950x, and the responsiveness is still bad, guess it still not enough for winui3😆

Edit: Curiously, if you move your mouse in vertical or horizontal motion, it performs OK. It only performs very poorly when you do a circular motion 😂

Start with the ColorPicker page in the WinUI 3 Gallery and reproduce the lag by dragging in a circle. Compare circular movement with horizontal and vertical movement, then trace the ColorPicker behavior responsible for tooltip and color updates. Done means responsive dragging and a consistently updating tooltip and color.

Written by the indexing model from the issue text.