hexify 0.2.0

• Added dggridR compatibility functions (as_dggrid(), from_dggrid())
• New hierarchical indexing support with H-index functions
• Improved coordinate conversion pipeline
• Added grid statistics functions

hexify 0.1.0

• Initial release
• ISEA discrete global grid implementation
• Support for apertures 3, 4, 7, and mixed 4/3
• Compatible with dggridR output