> Jevons paradox occurs when a more efficient use of a resource leads to an increase in its use

I think these are the same, because efficiency is value over cost. In the original formulation of the paradox, a more efficient steam engine lead to a rise in coal consumption. You can look at this as a "money buys coal, coal drives locomotion" system, where the latter part was improved. Modulo practical issues with coal (transport, storage, etc), dropping the price of coal would (probably?) lead to the same effect, since the end result is that locomotion per money is increased. For an outside observer, it doesn't matter if you get more coal per money or more locomotion per coal.

> standard supply and demand

Standard supply and demand doesn't say anything about increase of spend. If food prices drop, I'm not going to buy more food. I might buy better food for the same budget, but there's no reason why my total food spend should increase.

Hoarding out of fear of the price going up later due to tariffs or other economic instability/inflation. The Trump paradox?

Not for perishables, but for non-perishables.