Enable Light Mode on Battery

**Describe the enhancement or feature you'd like**
i actually want to make the app to enable Light Mode when unplugged, the opposite to enable Dark mode on battery option,

reason is simple, i have a 2k IPS Panel, and there is no efficiency gains in dark mode except having to increase brightness to see better
**Describe alternatives you've considered**

**Additional context**
Add any other context or screenshots about the feature request here.

Start by locating the existing implementation for enabling Dark Mode on battery and the entry point that responds to power-state changes. Done means the app enables Light Mode when unplugged, as the inverse of the existing option, while preserving current theme switching behavior.

Written by the indexing model from the issue text.