Regional terrain expansion

[I-am-Erk]

Summary

SUMMARY: Infrastructure "Adds a few more biome-dependent terrain types"

Purpose of change

#35627 adds the ability to specify terrain types by region. This is extremely useful for mapping and will allow maps to vary by biome, as well as limit needing long lists of terrain types in maps.

More specific subgroups of trees and flowers make it a little easier to use regional terrain in gardens and urban settings.

Describe the solution

Adds the following new pseudo-terrains:

• t_region_groundcover_urban - less dirt, no long grass
• t_region_tree_shade - fewer fruit and nut trees, no evergreens
• t_region_tree_fruit - all fruit trees all the time baby
• t_region_tree_nut - debated including non-edible nuts in these, settled on "a bit".
• t_region_tree_shade - decorative trees that don't drop as much junk on the ground for cleaning up
• t_region_tree_evergreen - pine and juniper currently
• t_region_shrub_fruit - all the berries
• t_region_shrub_decorative: Flower bushes
• f_region_flower_decorative: Garden flowers
• f_region_weed: no garden flowers

I am also experimenting with using these regional terrains to generate the list of cover for fields, forests, and such in the region. Seems logical, since they should also follow the regional breakdown and it will make it much more simple to create new biomes this way.

Describe alternatives you've considered

I'm sure there would be other ways to break these down, but this seems reasonable to me.

Testing

Tested. Doesn't throw errors. Fields don't look significantly changed by the adjustment in regional map settings, although they now spawn dead grass and there's a slight difference in the overall balance of terrain and furniture appearing of course.