v2.6.1

• New features
  • Add a Cell generation function
  • Add k-point generation functionalities
  • Add support to handle trajectory files
• Updated docs
  • Add a FOD optimization and a reduced density gradient example
  • Add references to data
• Miscellaneous
  • Breaking:
    • Rename X to pos in Atoms
    • Merge R into a in Atoms
  • Indicate Python 3.12 support
  • Support viewing multiple files
  • Support non-cubic cells in Atoms, io, and viewer functions
  • Support viewing multiple files
  • Fix Nix flake