Given that this page is mostly about the format of the save files, I'm not sure that it makes sense to have info about data contained within that format (e.g. PorchItem) as that is defined in, and created by, the game data and simply dumped into the existing format.
I don't have any better place to put it, though, so /shrug, I guess? The existing game data pages deal with formats of the data and the files, as well, not specific data contained within them. PorchItem should probably best go into a new Inventory page, but I don't know if it matters enough to bother.