Make sleeping in Inn more obvious

I created new versions of each skin, where the eyes are closed. Additionally the ZZZ displayed while sleeping have a white outline, which makes them more visible against dark backgrounds.

For screenshots of how this looks: https://github.com/HabitRPG/habitrpg/issues/3833

I will also create a second pull request in the habitrpg repo with the change for the avatar template, that is needed to display the closed eyes when sleeping