♿(Modal) h2 titles, dialog aria-labelledby, i18n close button

[Ovgodd]

Purpose

Improve Modal accessibility :

• expose a semantic title and correct dialog naming/description
• hide decorative title icons from assistive tech
• internationalize modal frame controls (close, back to tabs)
• add an accessible name for the DatePicker calendar popover

Proposal

• Render modal titles as h2 and name the dialog with aria-labelledby when a title exists.
• Link subtitles with aria-describedby in the default variant when present.
• Hide decorative title icons from assistive tech (aria-hidden on the icon wrapper).
• Use i18n strings for close and “back to tabs” controls.
• Add an i18n aria-label on the DatePicker calendar popover.
• Verify modal opens from trigger with role="dialog" and aria-modal="true".
• Verify pre-built modals (e.g. confirmation) still behave correctly; tests aligned with translated labels.