VerseRef.GetBBBCCCVVV does really unexpected things at the upper limit

I can't think of any scenario where using modulus to prevent a verse or chapter number from going out of range would give a a helpful result. Worse yet, at 999 (the purported max), we actually seem to have an unintentional off-by-one error, and 999 gets treated as 0. I would argue that if a verse or chapter number has been set to a value > 999, it should just be clamped to 999, in much the same way we are dealing with negative values.
It could possibly be argued that out-of-range values should throw an exception, or at least that a flag could be passed indicating whether the caller wants to clamp or throw.

Start at the VerseRef.GetBBBCCCVVV entry point and inspect how chapter and verse values are handled at the upper boundary, especially the modulus behavior at 999. Confirm the desired behavior for values above 999 and the existing negative-value behavior, then add or update boundary coverage so valid maximum values remain 999 and out-of-range values are clamped.