- Complete box-spout PHP 8 compatibility by adding return type declarations for CSV, ODS iterator classes
- Extend phpspreadsheet iterator patch to include RowCellIterator, RowIterator, ColumnCellIterator, and ColumnIterator classes
- Add mixed return type for current() and key() methods to comply with PHP 8.1+ Iterator interface requirements
- Add void return type for rewind() and next() methods
- Add bool return type for valid() method
These patches ensure full PHP 8 compatibility for third-party spreadsheet libraries used in ZenTao PMS.