{# Reusable modal shell.
Params:
body_template (required) template path for the modal body
title heading shown in the default header
max_width card width class (default max-w-lg)
card_extra_classes extra classes on the card
header_template optional full-bleed header; when set it replaces the
default title + close-button row (that header is then
responsible for its own close button)
footer_template optional full-bleed footer rendered below the body
body_wrapper_classes classes on the body wrapper (default generic-card-padding)
aria_labelledby id of the element that labels the dialog
#}
