BassClient: Add initial support for group operations

This add the mechanism for coordinated group operations
on BASS capable devices. It uses CAP context for discovering
device groups.

Adding source with group operation flag sets the sticky flag
on a particular device (and sourceId assigned as a result of
the add source request). After that, any modification on this
source or any BASS source on the other group member with the
same configured broadcast (since each device can assign a different
sourceId for the same add source request) results in such
modification being performed on each group member.

Sticky group flag is removed from each group member device
when removeSource() is called for a particular sourceId on each
device with the sticky flag already set.

Bug: 230559809
Tag: #feature
Sponsor: jpawlowski@
Test: atest BluetoothInstrumentationTests
Change-Id: Ia1d38777e08851c8c0ed49687d11dfbdd701b918