Prevent Fleet's arrows from passing through the stage#251

Fleet’s down air passes through platforms when used during the final frames before landing. This almost makes sense, and she can go pick these arrows up. However, the arrows also pass through solid ground onstage, where she can’t pick them up. This means that whiffing a down air will sometimes waste one of her stamina arrows, and it’s not easy to tell exactly what height will be safe. It’s not a big deal, but it doesn’t make sense to look at, and it makes instant float empowered bair unnecessarily risky in a weird way.