[Audiosharing] Handle auto start intent from QS

When intent extra EXTRA_START_LE_AUDIO_SHARING is true, audio sharing
page needs auto toggle on the main switch and start audio sharing.

And if there are one active sink and one connected sink, auto add source
to them without popping up dialog.

Test: atest
Flag: com.android.settingslib.flags.enable_le_audio_sharing
Bug: 331892035
Change-Id: I0c677ea33c9e0e3eeb8495c8618bff685b13a8ed