Earpiece switcher and overlay (#3347)

* Add a global control for toggling earpiece mode

This will be used by Element X to show an earpiece toggle button in the header.

* Add an earpiece overlay


* Fix header
The header needs to be passed forward as a string to some components and as a bool (hideHeader) to others.
Also use a enum instead of string options.

* fix top clipping with header


* hide app bar in pip

* revert android overlay app_bar

* Modernize AppBarContext

* Style header icon color as desired and switch earpice/speaker icon

* fix initial selection when using controlled media

* Add "Back to video" button

* fix tests

* remove dead code

* add snapshot test

* fix back to video button

* Request capability to learn the room name

We now need the room name in order to implement the mobile (widget-based) designs with the app bar.

* Test the CallViewModel output switcher directly

---------

Co-authored-by: Timo <toger5@hotmail.de>

src/index.css

@@ -45,6 +45,9 @@ layer(compound);
   --small-drop-shadow: 0px 1.2px 2.4px 0px rgba(0, 0, 0, 0.15);
   --subtle-drop-shadow: 0px 1px 2px 0px rgba(16, 24, 40, 0.05);
   --background-gradient: url("graphics/backgroundGradient.svg");
+
+  --call-view-overlay-layer: 1;
+  --call-view-header-footer-layer: 2;
 }
 
 :root,