[Task] Get CGs for Chapters 3 and 4

[alicerunsonfedora]

With changes coming up in Chapters 3 and 4 under the chapter3 branch, there are a couple of CGs needed:

• Alice CG for special route. Should be a similar scene to Yuri's CG, but from the opposite angle and prominently featuring an iPad mini on the desk. The keyboard should be a separate layer. Screens on iPad will be different layers as well.
• Alice CG for car scene. Should be CG inside of Alice's car, mostly viewing from front passenger's POV and looking at left side.

These CGs aren't necessary, but would be nice, too:

• Sayori CG for special route. Should contain Sayori and player drawing on construction paper.

For details, see story/chapter2.rpy and story/chapter3.rpy.