Downgrade Steam SDK version the game uses to avoid the incompatibilities a lot of people were having. We now only require SteamClient021, or Proton v9 or above.

Various minor fixes including:

• Fix R2 to speed up time not working after your first puzzle solve if you do skipping_stones first.
• Fix a spire remaining behind when the magistrate disappears after his monologue...
• Fix a camera issue with local area view and endpoint beams in wrapping levels
• Fix unlock and smash beam icons being visible in wrapping when they shouldn't be
• Fix z-fighting issue in promesst2
• Fix inability to undo while on a Rover sometimes
• Fix some bad checkpointing in a few Skipping Stones level
• Fix aspect ratio issues in a few levels
• Small art fixes to a number of levels
• Various fixes that seem too spoilery to put in patch notes...