Add audio playback capture method

Add a new method to capture audio playback.

It requires Android 13 (where the Shell app has MODIFY_AUDIO_ROUTING
permission).

The main benefit is that it supports keeping audio playing on the device
(implemented in a further commit).

Fixes #4380 <https://github.com/Genymobile/scrcpy/issues/4380>
PR #5102 <https://github.com/Genymobile/scrcpy/pull/5102>

Co-authored-by: Simon Chan <1330321+yume-chan@users.noreply.github.com>