Daytime window animation and transitions

[therationalpi]

There's a daylight background now, but the same space animation plays even though it looks like day. There should be a new animation, either a blue sky with clouds or some other brighter animation. Implementation should be similar to room_mask in script-ch30 with a looping webm file.

Additionally, when transitioning from daytime to evening and vice versa, it just pops in with no transition or dissolve.

[therationalpi]

Prototype for this being worked on by @monikLover . Current implementation uses an idiomatic renpy expression for movie failover to static image. This is preferred.

#46