If I understood you correctly: Aside from energy and cold, there's no other input that's really fundamental in the way you thinking. Most processes we consider "labor" consume energy and generate heat, and other than that deciding how to do things or where to source your energy/cold from is only a matter of efficiency. For material goods, you could always (with enormous difficulty/cost) create matter from energy, and arrange it the right way by "spending" some cold/negentropy, but if you want to make steel, mining abundant iron ore is much easier. If not:

Two people can exchange goods and both be better off, and that's the basis of trade.

We create valuable things where there were none (e.g. food, buildings, a concert) or make things more valuable by changing how accessible they are, moving them, changing their form, giving them to people who value them more, getting more information about them, etc. and we do all of this because each person doing it considers it better than not doing it. That's only because they get paid, usually, but that also happens because bosses consider paying workers to be better than not doing it. And so on.

I don't really get what you mean by "injecting value", but aside from food and steel you also value more abstract things like information, law and safety, consistency, personal connections, entertainment, and others. Every time service work happens, some of this kind of value is newly generated.