"All hands on deck" comes from the navy and is used by the captain of a ship to say something like "everyone on this ship must immediately come to the deck, as there is an important announcement or issue that we have to deal with". More generally it means everyone must focus, work hard, pay attention, that sort of thing. Talking about a woman being gorgeous, I guess it is a way of saying she is so gorgeous everyone had to pay attention or noticed her. This is a very unusual use of the phrase, it must be noted. I hope that is helpful.