[Feature Request] Add a ColorPicker Control

Although it's not as fundemental as having a control for getting numeric input (like a [Number box](https://learn.microsoft.com/en-us/windows/apps/design/controls/number-box), see https://github.com/dotnet/wpf/issues/2096 and https://github.com/dotnet/wpf/issues/8512 for related feature requests about it), there's currently no good way of letting user selecting a color (preferably with alpha channel info) without using a 3rd party library. If WPF had a control like WinUI's [Color picker](https://learn.microsoft.com/en-us/windows/apps/design/controls/color-picker), that would be really great.