macosx: Redesign music playback controls in audio decorative view

Moves the controls out of the way of the cover art, reduces their size, and adds constraints to ensure the cover art never covers the relevant controls/title bar/etc.

After changes:

Screen_Recording_2024-11-30_at_00.55.25

Before:

Signed-off-by: Claudio Cambra developer@claudiocambra.com