[Refactor] Add the gif-mode's rate that it spams the Sceenshot API at to be in the user's config

[alphastrata]

what are we refactoring?
gif_maker.rs / config.rs
So, this : app.insert_resource(Time::<Fixed>::from_seconds(0.05));
needs to not be a magic && should live in UserSession.

why?
because the framerate we allow capture at should be end user configurable.