improve godot tile system to increase fps

[rafaelcastrocouto]

• reduce number of tile layers
• auto bake static tile layers
• mipmap tiles acoording to the camera zoom

[WhalesState]

i don't know if canvas culling works by default for Tilemaps but maybe we can try to use visibility notifier.
https://docs.godotengine.org/en/stable/classes/class_visibleonscreennotifier2d.html
consider dividing the large maps into smaller ones first.