Not sure if there's any sort of manual anywhere, so asking here -

From what I can tell, upgrading the workshops opens up rare and legendary crafting recipes. Including loot. (Right?) So what happens to recipes I get, if I don't upgrade? or don't even build the room, yet? Are they hidden until I can unlock them? Or do they just disappear? I've collected a few, but they don't seem to be showing up anywhere.

I've upgraded my weapon workshop, but holding off on outfits, until I'm sure of where I want to build it. I'm playing on survival mode, so have to be very careful about where I put a level 3 room, and who I staff it with - so am I losing out on the outfit recipes I've been getting, or will they all be waiting for me, when I get around to upgrading?

Or are they listed somewhere in the Ui, that I'm overlooking?

No, you're good. You do not lose any recipe you collect before you have the corresponding workshop. They appear as you unlock the shop.

If you found a legendary outfit recipe, it will unlock as you build the outfit workshop and upgrade to the legendary level.

Confusing mechanic. Would make more sense to let us unlock them, but keep them greyed out with a listed room level requirement. That way, we'd know exactly what the deal is. Maybe even put recipes somewhere else, another collections or storage tab.