Request: Allow `with_show_button` slot of `Dialog` to be rendered with an `IconButton`

[khiga8]

Hello! Currently the Dialog has an optional with_show_button slot that can be rendered as Button to open the dialog. We ran into a case where we wanted the slot to be rendered as an IconButton. We were able to render this button standalone, but there weren't clear instructions around this. Given IconButton is a PVC component, I think it would be acceptable to allow consumers to specify that the with_show_button should be rendered as an IconButton.

Request:

• Add clear instructions for how a button can be associated with the dialog. (via data-show-dialog-id attribute)
• Allow with_show_button to be rendered as an IconButton.

Staff-only PR context