Add a browser confirm() dialog to the delete functions in UserEditModal,
PeerEditModal, and InterfaceEditModal to prevent accidental deletions.
The bulk-delete actions in UserView already had this protection; this
change brings single-item deletion in line with that behavior.
Translation keys (confirm-delete) added for all 10 supported locales:
de, en, es, fr, ko, pt, ru, uk, vi, zh.
Signed-off-by: LeC-D <leo.openc@gmail.com>
