kcms/workspace: describe visual options comprehensibly

Right now these settings are rather unclear, using vague language and omitting information about their scope. Let's re-word everything to make it clear to users what these settings actually do, and add context help buttons for more info if needed.

Eventually I want these settings to be moved or removed, but until then, we can at least make them easier to understand.

Before	After

@teams/usability @teams/vdg