Distinguishes a genuine audio mismatch at a clip boundary (evidence
the inputs aren't really a continuous sequence) from a boundary that's
simply too quiet to judge either way, using an RMS floor alongside the
existing cross-correlation confidence score. A confident mismatch now
aborts before encoding instead of silently splicing unrelated clips
together; --allow-discontinuous opts back into the old behavior.
Detects genuine audio/video overlap between consecutive Live Photo
clips via audio cross-correlation, trims the duplicated footage, and
re-encodes a seamless, metadata-preserving output.