v1.2.1

Hardening release.

Video sessions constructed with stableFrames above 16 could never turn stable when validity only emerged through frame fusion; the corroboration window now grows with the requested threshold.

Passing a rotation positionally in the stride slot (for example FromNv21(buffer, width, height, 90)) now produces an error message pointing at the rotation overload instead of a bare stride complaint. Unknown pixel layouts throw instead of silently reading as a black image. Small robustness guards in the tilt estimator and capture hint math.