[OutputSwitcher] Add "Share audio" button and click to open settings

"Share audio" button is displayed when it is available to start audio sharing, "Sharing audio" button is displayed when doing audio sharing. Clicking the button will open the audio sharing settings page.

Bug: 423772889
Test: atest MediaSwitchingControllerTest / BluetoothUtilsTest
Flag: com.android.systemui.enable_output_switcher_audio_sharing_button

Change-Id: Ie6b30c11ee61d8725eb815f2df84c1839f83e787