Dynamic top Appbar background color

**Is your feature request related to a problem? Please describe.**
...

**Describe the solution you'd like**
Hi! I would like the top Appbar background to behave according to [this MD3 guideline](https://m3.material.io/components/top-app-bar/guidelines#4eab4f50-4a3e-4189-bce2-a46514cde1da):

https://github.com/callstack/react-native-paper/assets/56068232/48ac7a36-e03b-42ac-b437-97e4c8c209ad

**Describe alternatives you've considered**
...

**Additional context**
..

Start by locating the top Appbar component and its existing background-color behavior, then compare it with the linked Material Design 3 guideline and the attached example. Done means the top Appbar background changes according to that guideline, with coverage added for the resulting behavior if the component has tests.

Written by the indexing model from the issue text.