Snap transforms to pixels

[manuq]

This is a recommended setting for low resolution pixel-art games. Exactly this case. It will help instantiating Player or Goober scenes directly into the canvas.

Helps #34

[manuq]

See docs: https://docs.godotengine.org/en/stable/classes/class_projectsettings.html#class-projectsettings-property-rendering-2d-snap-snap-2d-transforms-to-pixel

[wjt]

With this PR:

Screencast.from.2025-01-28.15-45-52.webm

And without it:

Screencast.from.2025-01-28.15-47-14.webm

I find the stuttering motion with this PR quite unpleasant to look at. That's consistent with the documentation:

This can lead to a crisper appearance at the cost of less smooth movement

So personally I think we should not make this change.

[manuq]

OK @wjt ! Per the GDD this is "retro, pixel-art visual style and feel" so I thought it was worth adding. But many retro-like games are flexible on things like this, in unlimited palette, etc. So I'll close it.

The other thing that this helps is in avoiding subpixel interpolation when instantiating scenes and positioning them in the canvas. But for that there is the "snap to pixel" canvas option which is turned on by default.