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/AppBar.test.tsx

@@ -0,0 +1,25 @@
+/*
+Copyright 2025 New Vector Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { render } from "@testing-library/react";
+import { describe, expect, it } from "vitest";
+import { TooltipProvider } from "@vector-im/compound-web";
+
+import { AppBar } from "./AppBar";
+
+describe("AppBar", () => {
+  it("renders", () => {
+    const { container } = render(
+      <TooltipProvider>
+        <AppBar>
+          <p>This is the content.</p>
+        </AppBar>
+      </TooltipProvider>,
+    );
+    expect(container).toMatchSnapshot();
+  });
+});