PaddleOCR returns multi-word blocks (whole phrases), so ALL inter-word
gaps in small zones (boxes, ≤60 words) are column boundaries. Previous
3x-median approach produced thresholds too high to detect real columns.
New approach for small zones: gap_threshold = max(median_h * 1.0, 25).
This correctly detects 4 columns in "Pounds and euros" box where gaps
range from 50-297px and word height is ~31px.
Also includes SmartSpellChecker fixes from previous commits:
- Frequency-based scoring, IPA protection, slash→l, rare-word threshold
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>