v1.6.0

Changes

• Fix FMT-009 false positive: Spacing detector now measures inter-block baseline gaps, correctly detecting double spacing in PDFs that encode each visual line as a separate text block. Previously only measured intra-block gaps, causing nearly all briefs to be flagged as single-spaced.
• Page references in report: Failed check cards now show page number badges identifying which pages have issues. Passed checks table includes a Pages column.
• Engine footer: Report footer now indicates whether PyMuPDF was used or fallback mode was taken.
• Data model: Added pages field to CheckResult and pymupdf_used field to ComplianceReport.
• CLI: Added --pymupdf/--no-pymupdf flags to build_report.py.