Add city block

[curstwist]

Summary

SUMMARY: Content "Adds a 4x1 mixed use city block."

Purpose of change

Begin expanding city center locations to include more dense, urban locations. Meant to be a test using nested mapgen to create variable urban environments, I'll need to add more blocks for it to reach its full potential, however they are pretty nice as stand alone spawns.

Describe the solution

Adds a 4x1 city block consisting of 8 retail/commercial spaces and 8 upper level apartments.
The residential spaces use the already existing house/domestic nested chunks for most of their mapgen.

I've added a substantial number of retail themed nests for the lower floors.
6 retail shops
3 restaurant types
4 clothing store types
also nests for back room areas, that vary with offices, workrooms, employee areas, storage.

Describe alternatives you've considered

I've stopped to PR due to its size (mostly for nested chunks). I still plan to add more variants to the commercial spaces. Some only have 1 option atm.

I still need to add the roof and I'm considering sub-0 spaces.
I'll add some vehicle spawns in the alleys when I add roofs.

note to reviewers:
I'm using a palette for the building foundation but I'm opting to define things individually in the chunks so I can have greater floor variability and duplicate furniture spawns for look placement as needed.

Testing

repeated testing by debug spawn in the world and spot checking worldgen spawns.

Additional context

With all the nested chunks, it's difficult to convey the entire mapgen, so here are some sample spaces:

western end:

center

eastern end:

2nd floor:

[I-am-Erk]

Love it