Tell player when a recipe is available because of an NPC

[ChucklesTheBeard]

Is your feature request related to a problem? Please describe.

When a recipe is available, but isn't memorized, it shows the text

Recipe not memorized yet
Written in:
<list of books the recipe is in>

... but if the recipe is available because there's a friendly NPC nearby, the list may be empty, so it shows up like this:

Describe the solution you'd like

The list of books it's written in should also show up here, but not unless it's actually written in a nearby book.

Additional context

No response