[FEATURE]: Add accessibility packages

[e-perl-NOAA]

I'm not sure of all the accessibility features/packages available to make shinyapps more accessible but there was a demonstration with a GitHub repo at ShinyConf2025 that has several examples.

Accessibility packages:
{shinya11y}: creates an overlay to review how accessible your shiny app is.
{BrailleR}: provides support for blind users
{sonify}: creates sounds in the shape of charts.
{tactileR}: create tactile charts.