Use checkboxes for boolean example UI

> Just curious, for boolean settings like this, why not checkboxes?

Honestly that didn’t even cross my mind until just now! I was just driving on autopilot to use radio, but you’re right that I could be using checkboxes for these. It can be something I’ll circle back to after I finish all the examples

_Originally posted by @kfc35 in https://github.com/bevyengine/bevy/issues/25131#issuecomment-5053792648_

Start from the boolean example UI discussed in issue #25131 and locate the example source that currently uses radio controls. Compare the existing checkbox usage in the UI examples, then update the boolean settings examples so their controls are checkboxes and verify the examples still build and display correctly.

Written by the indexing model from the issue text.