Spreadsheet Forensics Engine

 Build an advanced spreadsheet forensics engine that analyzes complex Excel workbooks. Detect hidden sheets, unusual formulas, broken references, inconsistent formulas, duplicated calculations, circular dependencies, hardcoded values inside formula regions, suspicious formatting changes, unused ranges, and calculation chains. Construct a dependency graph showing how important outputs are calculated. Produce an audit report explaining which cells deserve human review and why, while preserving the original workbook.