Run a Capacitor plugin on a different thread in Android

runOnUiThread should be used to run things on the UI Thread, for updating native views and such.

For just using the main thread you can do something like:

@PluginMethod
public void play(PluginCall call) {
    new Handler(Looper.getMainLooper())
        .post(
            () -> {
                audioPlayerService.play(audioId(call));
            }
        );
    call.resolve();
}