Changes in version 0.2.1 (2026-05-13)                  

  - Addressed CRAN comments re version 0.2.0.

                        Changes in version 0.2.0                        

  - avg_alpha() now uses a compiled C++ rarefaction routine
    (rrarefy_cpp) in place of vegan::rrarefy(), yielding roughly a 34%
    end-to-end speedup.