The Scripture reference whose book is to be adjusted.
The number of books to offset the current book by. Positive values move forward, negative values move backward.
A new Scripture reference with the adjusted book. The chapter and verse numbers are
reset to 1. If the resulting book number exceeds the bounds of available books, it is clamped
to the nearest valid book. For books-present-aware stepping that rolls across chapter/book
boundaries (Paratext 9 style), see the get*Ref navigation functions in
platform-bible-react/experimental.
Adjusts the book of a Scripture reference by a specified offset.