[Task] Fix UI quirks

[PennRobotics]

• gap in horizontal lines in gridview (text entry for manual gain was expanded without also expanding grid size, lines do not automatically expand to fill space; both of these should resolve this)
• thumb center is not correct
• make the slider background a shaded color to make it more intuitive
• monitor mix needs to be more intuitive
• grey the EQ text when EQ is disabled
• maybe make each panel's background light grey until the mic is connected?
• bring back indeterminate controls??
• show clock, status bar, etc.
• use maxwidth so that landscape mode and tablet don't look totally ridiculous?
  • alternatively, other view methods e.g. constraint