docs: more details about only_shiny

fix #340

Author: davidgohel

DESCRIPTION

@@ -1,7 +1,7 @@
 Type: Package
 Package: ggiraph
 Title: Make 'ggplot2' Graphics Interactive
-Version: 0.9.3.003
+Version: 0.9.3.004
 Authors@R: c(
     person("David", "Gohel", , "david.gohel@ardata.fr", role = c("aut", "cre")),
     person("Panagiotis", "Skintzos", , "sigmapi@posteo.net", role = "aut"),

R/girafe_options.R

@@ -268,7 +268,12 @@ opts_hover_theme <- function(css = NULL, reactive = FALSE) {
 #' [girafe_css()], to give more control over the css for different element types.
 #' @param type selection mode ("single", "multiple", "none")
 #'  when widget is in a Shiny application.
-#' @param only_shiny disable selections if not in a shiny context.
+#' @param only_shiny disable selections when not running within a Shiny
+#' application. Defaults to `TRUE` because selection is primarily
+#' designed for Shiny interactivity, where selected elements can be
+#' captured as reactive values. Set to `FALSE` only to demonstrate
+#' the selection/lasso feature in standalone HTML pages (e.g. in
+#' documentation examples or R Markdown output).
 #' @param selected character vector, id to be selected when the graph will be
 #' initialized.
 #' @note **IMPORTANT**: When applying a `fill` style with the `css` argument,