PrimaryBody and SecondaryBody colors for theme

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For my project I am currently writing a style for RadioButton that is styled as a ChoiceChip (https://material.io/components/chips#choice-chips)
Currently I have the following result:

As you can see the light theme is nice, but unfortunately the foreground color of the dark theme does not have enough contrast.
The problem is that for light theme I need the foreground to be PrimaryHueDarkBrush, but for the dark theme it must be PrimaryHueLightBrush. (Same for Secondary)
I currently think the best way to achieve this is by introducing a PrimaryBody and SecondaryBody color to the theme. The naming because it reacts in a similar way as currently the MaterialDesignBody color does.

I am willing to look into creating a PR with the necessary changes if you also see this as a good solution. Otherwise I hope you can come up with a better solution to fix this issue.

Beginne damit, das bestehende Verhalten der Theme-Farben für PrimaryHueDarkBrush, PrimaryHueLightBrush, Sekundärfarben und MaterialDesignBody zu überprüfen. Verfolge, wie ein als ChoiceChip gestyltes RadioButton die Vordergrundfarben in hellen und dunklen Themes auswählt, und überprüfe anschließend, ob das vorgeschlagene Verhalten von PrimaryBody und SecondaryBody in beiden Themes ausreichenden Kontrast bietet.

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