Add more nests to the roof palette

[Milopetilo]

Summary

Infrastructure "Roof palette has more built-in nests"

Purpose of change

Noticed some roofs used symbols for adding nests that were already in use by roof_palette and so sometimes spawned furniture instead of nothing. This also adds water heaters to roof_palette and cleans up a roof nest.
This also fixes an issue where motels spawned with solar panels in the windows.

Describe the solution

Add most nests available in nested_chunks_roof to roof_palette. Go over every usage of the palette to make sure no overlap happens and change the symbol if it does occur.

Describe alternatives you've considered

Go over every roof and make sure no symbols overlap with the palette.

Testing

Game loads, roofs look the same and don't have nests erroneously.

Additional context

Will follow this up with making all roofs use the nests introduced here.