This navbox goal is to mimick the game build UI in what categories and items are shown.
Dev notes
- Game orders category just by declaring them in order in data.categories
- Order within a category seems to be done with some "id" of who registered first? Not implemented here.
- (but if we need that, maybe it's enough to just add an ordering field with the same logic as the one for filter categories.)
- In game code, BuildView.lua is where most of the stuff happens
- Game filters entities by:
- only stuff that is unlocked by faction
- `if not frame_def.construction_recipe then return end -- not a building` -> This one matches our `entity.recipeType != Construction` in the sub template (BuildingsNavCat)
- `if not bp_frame_def and not def.visual then return end -- no default visual` -> Extract code already skips this