More options to place the Island on screen

### Feature Description

Add more option to place the Island on the screen:
- at the top right/left
- at the bottom center/right/left.

### Use Case

It will allow more choices for the user, and for example to have the Island placed at the top left corner of the screen.

### Compositor(s)

All compositors

### If Other, please specify

_No response_

### Proposed Solution

_No response_

### Alternatives/Existing Solutions

_No response_

Start by locating the Island's current screen-position setting and the compositor layout entry points. Review how placement is selected for all compositors, then support the requested top-left, top-right, bottom-left, bottom-center, and bottom-right choices and verify each placement.

Written by the indexing model from the issue text.