♿️(menu) add opensInNewWindow for external link aria-label

[Ovgodd]

Purpose

Improve dropdown and context menu accessibility for screen readers when items open external links
When a menu item opens a link in a new page or tab, screen readers must announce it:

• announce “(new window)” without changing the visible menu label (DSFR / RGAA pattern)
• keep label as the only visible text for menu items
• provide an i18n-backed aria-label suffix for supported UI Kit locales

Proposal

• Add opensInNewWindow?: boolean on MenuItemAction
• Append an i18n suffix to aria-label when enabled
• Add components.menu.newWindowLabelSuffix in en-US, fr-FR, and nl-NL

Dom example :

Usage (Docs)

{
  label: t('Documentation'),
  opensInNewWindow: true,
  callback: () => openExternalLink(documentationUrl),
}