Use transparent clear color during animation

If fillColor property is used on Safe Items, then the item is cleared by using the fillColor. This is however not compatible with animation as it would result in colored rectangles around the screen when the item is moved.

The solution seems to be to disable the fillColor during transition animation and use transparent clear color instead. The fillColor should then again be used, when the icon is at its destination.

Animation also makes the output verification impossible for moving items as the background layer behind safety layer shows up and makes it impossible to know the correct CRC of the area.

 
Definition of Done

1. Implementation done
2. Unit tests are implemented
3. Quality gates passed (reviews, coverage, optionally CVE).
4. TestRail entry done
5. API documentation done, comments added in code.
6. Architecture documentation is updated.
7. Design documentation is updated.