Audio device controls for mobile native audio device selection

Backport of 0971a15c40.

src/state/MuteAllAudioModel.test.ts

@@ -0,0 +1,36 @@
+/*
+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 { test, vi } from "vitest";
+import { expect } from "vitest";
+
+import { setAudioEnabled$ } from "../controls";
+import { muteAllAudio as muteAllAudioSetting } from "../settings/settings";
+import { muteAllAudio$ } from "./MuteAllAudioModel";
+
+test("muteAllAudio$", () => {
+  const valueMock = vi.fn();
+  const muteAllAudio = muteAllAudio$.subscribe((value) => {
+    valueMock(value);
+  });
+
+  setAudioEnabled$.next(false);
+  setAudioEnabled$.next(true);
+  muteAllAudioSetting.setValue(false);
+  muteAllAudioSetting.setValue(true);
+  setAudioEnabled$.next(false);
+
+  muteAllAudio.unsubscribe();
+
+  expect(valueMock).toHaveBeenCalledTimes(6);
+  expect(valueMock).toHaveBeenNthCalledWith(1, false); // startWith([false, muteAllAudioSetting.getValue()]);
+  expect(valueMock).toHaveBeenNthCalledWith(2, true); // setAudioEnabled$.next(false);
+  expect(valueMock).toHaveBeenNthCalledWith(3, false); // setAudioEnabled$.next(true);
+  expect(valueMock).toHaveBeenNthCalledWith(4, false); // muteAllAudioSetting.setValue(false);
+  expect(valueMock).toHaveBeenNthCalledWith(5, true); // muteAllAudioSetting.setValue(true);
+  expect(valueMock).toHaveBeenNthCalledWith(6, true); // setAudioEnabled$.next(false);
+});

src/state/MuteAllAudioModel.ts

@@ -0,0 +1,19 @@
+/*
+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 { combineLatest, startWith } from "rxjs";
+
+import { setAudioEnabled$ } from "../controls";
+import { muteAllAudio as muteAllAudioSetting } from "../settings/settings";
+
+/**
+ * This can transition into sth more complete: `GroupCallViewModel.ts`
+ */
+export const muteAllAudio$ = combineLatest(
+  [setAudioEnabled$.pipe(startWith(true)), muteAllAudioSetting.value$],
+  (outputEnabled, settingsMute) => !outputEnabled || settingsMute,
+);