GitLab

- Implement xycut algorithm to sort blocks when layoutreader fails
- Add recursive_xy_cut function to perform the xycut algorithm- Update pdf_parse_union_core_v2.py to use xycut when layoutreader fails
- Modify draw_bbox.py to handle cases where layoutreader fails to sort blocks

Adapt import statements in `pdf_parse_union_core_v2.py` to reflect the updated packagestructure, changing from the `magic_pdf.v3.helpers` module to the `magic_pdf.model.v3`
module. This ensures compatibility with the revised directory layout.