V4.2605.05

• ⛓️‍💥 Breaking Change(s)
  • Removal of GetSheetFileName(int offsetSheetId);
  • Removal of GetDefinedRange via int sheetId
  • Removal of Index property from ISheet
  • Internal Creation of WorkBooks
  • Internal implementation of IOpenXmlWorkBookReader::GetSheetNames now returns the relative path to the "Sheet Name"
  • CellValue is now a class, therefore no need to use .Value
  • ICell.CellValue is now nullable
• ✅ Cell object type 📅
  • ✅ "Best Effort" Operator based conversion
  • ✅ TryGetType will return out type, if stored as that type.
  • ✅ Unit Tests
• ✅ Performance
  • ✅ Use ValueTask and reduce memory allocations in some hot paths
  • 🚀 Fix fallout from making CellValue is now a class
  • ✅ ArrayPool support has been added to ThreadStringBuilderPool using ArrayPool.
  • ✅ Release-specific optimizations added
    • ✅ EnableTrimAnalyzer: true
    • ✅ TieredCompilation: true
    • ✅ TieredCompilationQuickJit: true
    • ✅ TieredCompilationQuickJitForLoops: true
• ✅ Implement System.DBNull return option, for empty cells
  • ✅ Implement INullRow return option, for empty rows
  • ✅ Update tests to use INullRow detection
• ✅ Implement GetCell###(string columnLetters, ...) #8
• 🚀 2026-05-05