fix(Link): ensure target _blank is flagged as external for Inertia

[Barbapapazes]

Hello 👋,

This PR fixes a bug where the following button:

<template>
  <UButton
    href="/admin"
    target="_blank"
  />
</template>

triggers an Inertia request, opening the link in an Inertia modal instead of a new tab.

This happens because a blank target is not treated as an external link, and Inertia ignores the target prop. As a result, Inertia fetches the URL, returns HTML, and displays it in the modal.

[pkg-pr-new]

npm i https://pkg.pr.new/@nuxt/ui@4746

commit: 6595275