LeAudioTestApp: Split and present BIS, ENC, PA states

Unified statuses represended by single value and further handled by
string was not covering all cases. There were possibility that remote
was no longer synced to PA but synced to BIS. In this state there were
no possibility to force stop synchornization via UI due to BIS synced
state. This CL also helps presenting more detailed state of
synchronization and encryption of BIG.

Tag: #feature
Bug: 301201796
Test: manual test of LeAudioTestApp with BASS
Change-Id: I0b995b076b79c91354715feaa0275234dd42f82e