Resubmission addressing the CRAN reviewer's comments on the 1.0.0 submission, with a bug fix folded in.
\dontrun{} examples that called the unexported internal
functions plot_ras_scan() and plot_ras_zoom_regions() through :::.
These functions are internal (@keywords internal) and are already exercised
by the runnable example of the exported plot() method for "ras" objects.ras_memory() "abort" example runnable by wrapping the intentional
stop() in try(), instead of hiding it in \dontrun{}.on.exit(par(oldpar)), so plotting a "ras"
object no longer leaves the user's par() settings modified.screen_forward_max_region() (and therefore ras()) when
covariates contained missing values. Incomplete cases are now dropped before
the model matrix is built, matching the documented "removes incomplete cases"
behaviour, on all three scan paths (continuous exact-FWL, binary score, and
the legacy glm path).