Fix dplyr deprecation issue (#107)

* minor fixes to remove NOTEs from check

* fix CRAN check errors: replace defunct dplyr functions, fix Rd docs

Replace defunct dplyr functions (group_by_(), arrange_(), do()) with
modern equivalents using .data pronoun. Fix \itemize Rd markup to use
\describe with proper \item{name}{description} syntax. Remove broken
\link{sim_data} cross-references. Bump version to 1.2.4.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* add workflow_dispatch trigger to R-CMD-check

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

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Co-authored-by: roninsightrx <ronkeizer@gmail.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

update cran comments

Merge pull request #40 from TPreijers/master

Changes to sim-indexing function

bump version and correct R dependency (dplyr requires R >= 3.0.2)