LPS-30949 Ask user for each necessary confirmation when moving an event to trash

Also, messages were updated so now they say the event is going to be "moved to trash" instead of being "deleted"
LPS-30949 Regenerate
LPS-30949 Using an object to carry user's decisions across callbacks on edit dialogs

With this change, we could remove redundant code and two ad hoc parameters from askUserConfirmations.
The CalendarUtil methods for persistence could also be deleted, which is good because they were most
of the time the call of the same method with different parameters.
LPS-30949 Extracting edit confirmation dialogs to their own methods
LPS-30949 Extracting delete confirmation dialogs to their own methods
LPS-30949 Invited resources will be notified when deleting all instances following the first one

Also, closing the first panel after contacting the server to avoid an annoying blink.