Redesign sound settings icon and page

[eLtMosen]

• Implements a dconf value to track the preMuteVolume so that it can be restored system wide on un-mute
• Sound settings page icon changed to a large outline speaker in same size like the other icons in that listview
• Icon in sound page is now a mute toggle button and shows the volume in 4 stages
• Made the sound settings page design consistent with the bluetooth settings page
• Volume increase/decrease buttons un-mute when pressed while muted.

Depends on actually adding the icons in https://github.com/AsteroidOS/asteroid-icons-ion/pull/16 Contributes to completing https://github.com/AsteroidOS/asteroid-settings/issues/76

https://user-images.githubusercontent.com/15074193/234376496-695ff4e0-afff-4f57-8642-ac89c8c07ae1.mp4

The new sound settings icon