This allows to dynamically add clients when an event is received from an unknown IP address.
The user is asked to confirm any unknown connection from new clients.
Currently the back-ends for event producing and consuming are not yet notified, so events will not be received and sent to the newly created clients.
To reduce binary size one can now enable only specific backends, e.g.
wayland or x11 via cargo features
Additionally adds stubs for libei and xdg-desktop-portal backends
