Add option to Oracle to only display foods in Diary & favourites

The Oracle is a great feature in theory, but in reality it is mostly not very useful as it tends to present a list of lots of foods I don't have in stock and often things I don't typically eat.

It would be extremely helpful to be able to filter results to display only things already in my food Diary or favourites, so that I'm presented with a list of things I'm much more likely to: a) have in stock at home, and b) enjoy eating (and in my case specifically, as someone with food intolerances, food I can actually eat!).