Get rid of internal library code and use pulsectl library to communicate
with PulseAudio server.
This is a breaking change as the library uses the much more powerful
native interface instead of the CLI interface, requiring the need to
change the default port.
On the bright side, this also solves some issues with the existing
implementation:
- There was no test if the complete list of loaded modules was
already received. If not all data could be read at once, the
remaining modules not yet in the buffer were considered absent,
resulting in unreliable behavior when a lot of modules were loaded
on the server.
- A switch could be turned on before the list of loaded modules was
loaded, leading to a loopback module being loaded even though this
module was already active (#32016).
