libnotificationmanager: Add default parameters for actions in WatchedNotificationsModel for QML
Currently when invoking actions of a notification in a WatchedNotificationsModel in QML (ex. lockscreen in Plasma Mobile), we get something along the lines of Error: Unknown method parameter type: Notifications::InvokeBehavior
.
Add default parameters for the action invoking functions to match notifications.h
https://invent.kde.org/plasma/plasma-workspace/-/blob/master/libnotificationmanager/notifications.h#L451 so that we can call these functions in QML.
This fixes lockscreen notifications not having their actions invoked in Plasma Mobile.
Edited by Devin Lin