DocVortex 0.4.8

Changes

• Fix native PDF spatial layout: local column detection for reference regions, standalone formula bands with side numbering, boxed table captions, and figure legend recovery with unified attribution.
• Improve title recognition: column-head and near-full-width small titles, multi-line centering evidence, and small-font bold titles identified by relative size and independent spacing.
• Preserve member ownership in text assembly: same-line fragments and inline math members survive semantic merging, and paragraph boundary evidence carries through page merging.

Full Changelog: v0.4.7...v0.4.8