feat: add Outdoor Clean Theme

[rhaen]

All Submissions:

• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Yes checked it. This is a new theme that provides a better visibility outdoors, especially for those who want to look at telemetry data in the flight (like RC planes).

New Theme Submissions:

Have you included all the required elements?

1. Have you included all the required elements in your theme?
2. Are your screenshots in the correct resolution?

UV doesn't throw any errors. Screenshots are in 480x320.