Don't pass the ucred to the client construct, just set the properties
in the protocol.
Use the client properties to get ucred.
Add the security label to the client properties (from SO_PEERSEC)
Make some more varargs error functions
Make pw_resource_error always just send the error to the resource id.
Make sure we send errors to the right destination.
Add proxy error event and emit it when the core finds an error for
the given proxy id.
The client error is supposed to be sent to all resources of a client
for the given global.
Rename the flatpak module to access module. The access module should
either let the client connect or mask the client busy while the
permissions are being configured. It is then up to the session manager
to collect the right permissions of the objects and configure those
in the client.
Let the media session monitor the clients and configure the permissions.
