Add ability to hide icons in the Running Apps Widget

### Feature Description

You can adjust the size of the icons, but you can't make them disappear completely.

It would be nice to be able to do that and just have the text (title of the app). I also thought that if there is no icon, the text should be centered.

### Use Case

_No response_

### Compositor(s)

All compositors

### If Other, please specify

_No response_

### Proposed Solution

_No response_

### Alternatives/Existing Solutions

_No response_

Start by locating the Running Apps Widget implementation and its existing icon-size control. Add a way to hide the icons while keeping app titles visible, and verify that titles are centered when no icon is shown across the supported compositors.

Written by the indexing model from the issue text.