Dialog: Add a way to cancel closing (e.g. for unsaved changes)

[ataylor32]

Looking at the "Dialog" documentation, there doesn't appear to be a way to configure a dialog so that if the user tries to close the dialog (using the close button or escape key or whatever) then that can be interrupted with a confirmation.

Here's an example of a confirmation appearing on Facebook when closing an "Edit post" dialog:

Confirm.mp4

I would like to recreate this behavior with a PrimeVue dialog for not just the close button, but also the escape key or clicking the modal background.