Add effect sizes, tests, and CI workflow

[M-Colley]

Summary

• add opt-in package loader, clipboard-safe utilities, and effect-size reporting for NPAV variants
• create a comprehensive testthat suite covering every helper plus supporting helpers for sourcing
• add a GitHub Actions workflow that installs required R packages and runs the tests on every push/PR

Testing

• Not run (R is not available in the execution environment)

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Codex Task

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Run dependency install step inside R

The workflow step that is supposed to install the R packages (lines 15‑20) runs install.packages(...) as a plain shell command. GitHub Actions steps default to bash, so the runner throws install.packages: command not found before any dependencies are installed or tests run. Wrap the installation in an R invocation (e.g. Rscript -e 'install.packages(...)' or shell: Rscript {0}) so the command executes inside R and the job can proceed.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Workflow omits easystats required during tests

In the helper (tests/testthat/helper-r_code.R:2) the tests disable automatic installation, yet r_functionality.R still executes library(easystats) (line 57). The workflow’s dependency list (lines 17‑20) never installs easystats, so sourcing the file immediately errors with “there is no package called ‘easystats’” and the suite never runs. Ensure that easystats (and any other packages loaded unconditionally) are installed in this step before sourcing the script, or stop disabling auto installs for the workflow.

Useful? React with 👍 / 👎.