[Feature] Floating "Volume Mixer" Improvements (e.g. Dynamic Layout)

[Coldblackice]

Currently, EarTrumpet's floating "Volume Mixer" popup displays all audio devices along a single row only, necessitating lots of scrolling for any that have a number of audio devices. Some ideas to improve this:

• Dynamic layout of Volume Mixer
  Like a CSS "float", the volume-mixer could allow for displaying additional rows, the layout could dynamically adapting to the constraints of the window, e.g., user resizes mixer panel from a rectangle shape to a square --> panel adapts by displaying devices along an additional row(s)
• User rearrangement of devices
  Ability to mouse-drag devices around in the panel to rearrange ordering, allowing for most pertinent devices to be displayed at the front
• Remembering mixer scroll position
  Each time the volume-mixer is closed, the scroll position gets reset back to the start. Optionally, the scroll position could be remembered for next time the mixer opens, given it's likely the user will be changing the same device's app volumes