If we have properties, strtok will return strings from there as tokens
and the error will appear later as we will attempt to parse an incomplete
GVariant. It is better to catch this early so that we can print a more
useful error message.

So now we can do:
---
load-module C foo {
  "property": <"value">
}
---

The starting brace is still required to be on the same line
as the load-module.

Properties are expected to be a GVariant a{sv} dictionary,
specified in the GVariant text format:
https://developer.gnome.org/glib/stable/gvariant-text.html

Unregister fixes

See merge request gkiagia/wireplumber!14

This is a bit of a hack, temporarily needed for AGL.

Async endpoints

See merge request gkiagia/wireplumber!13

Currently this will just grant full access to all clients.
A future version will refine that to grant access to specific
objects only.

Registry

See merge request gkiagia/wireplumber!12

Fixes #1

This is a situation that always happens on startup, so let's not
spam with warnings

signal emission apparently does not work in _finalize()

Fixes some critical warnings from remote-endpoint.c because disconnection
from the destroyed endpoints did not happen

Proxy global id

See merge request gkiagia/wireplumber!11

spa audioconvert (the backend of audio-dsp) does not adevertise
property changes, therefore subscribe_params() is useless.
In order to get the real value from the node we need to call
enum_params() manually.

https://github.com/PipeWire/pipewire/issues/157

This provides high level volume controls for the AGL audiomixer
binding and the applications using it.

We now have always a "selected" endpoint for each direction (source, sink)
that is picked as the first available endpoint at startup,
and it changes automatically if the currently selected endpoint is removed

This avoids the theoretical crash that would happen if you change
the control value on an endpoint whose client-endpoint proxy has
already been destroyed