CmdPal/Dock: Automatic foreground with custom background can make UI illegitable

### Microsoft PowerToys version

0.98

### Installation method

Dev build in Visual Studio

### Area(s) with issue?

Command Palette

### Steps to reproduce

I've set the dock background color to black to blend with the monitor edge. After accidentally triggering the light switch and changing the theme from dark to light, the labels are now black on black, making the dock unusable.

#blameLightSwitch #notReally #justJoking

### ✔️ Expected Behavior

_No response_

### ❌ Actual Behavior

_No response_

### Additional Information

_No response_

### Other Software

_No response_

Reproduce the issue in Command Palette by setting a black dock background, switching from dark to light, and observing the labels. Trace how the dock chooses foreground colors after the theme change; done means the labels remain legible with the custom background.

Written by the indexing model from the issue text.