Update: Habitat arcology project now requires only arcology ascension perk.
更新：现在居住站理想城计划只需要理想城飞升。

If you somehow get the size of habitat above 8, you can still enact the project with 8 districts. But you will only get 4 habitat arcologies regardless.
如果用魔法把居住站大小调高，还是只需要8个居住区划。但是计划完成后不管如何只会有4个太空居住理想城

Now the project requires the habitat to have at least 8 habitation districts.
现在需要在居住站上有至少8个居住区划才能变为理想城。

Increased housing for all district.

Added feature: prosperity tradition perk that gives housing new add +2 housing to Habitation District.