[DarkMode] TaskDialogs should respond to System: DarkMode and Application's SystemColorMode.Dark

### .NET version

9.0.100-rc.2.24455.8

### Did it work in .NET Framework?

No

### Did it work in any of the earlier releases of .NET Core or .NET 5+?

No

### Issue description

**2 cases:**
1. TaskDilaogs are not in dark mode when enabled Dark mode in System and setting Application.SetColorMode(SystemColorMode.System)

https://github.com/user-attachments/assets/914450af-ebeb-42d5-aa85-df4b1913f505

2. TaskDialogs are not in dark mode when setting Application.SetColorMode(SystemColorMode.Dark)

https://github.com/user-attachments/assets/36ae44c3-0121-42ae-9bdc-c7e1f2e2e3c9

### Steps to reproduce

[TaskDialogSamples.zip](https://github.com/user-attachments/files/16902188/TaskDialogSamples.zip)