Dialog: no DialogDescription — stacked title + description requires a hand-rolled wrapper

[krnvch]

Summary

DialogHeader is DrawerHeader re-exported and lays its children out in a row (title + close ✕). There is no DialogDescription component, so a dialog with a description under the title (a common Figma pattern, e.g. the delete-account confirm in Platform Auth 553:1556) forces every consumer to hand-roll the stacking:

<DialogHeader>
  {/* DialogHeader lays children out in a row; stack title + description
      in a column so they sit tight instead of the description landing
      in the header row. */}
  <div className="flex flex-col gap-4">
    <DialogTitle>Delete account?</DialogTitle>
    <Text size="sm" color="secondary">You will lose access…</Text>
  </div>
</DialogHeader>

Live occurrence: core-frontend DeleteAccountDialog (flagged in core-frontend MR !156 review as tricky consumer-side code that belongs in the DS).

Proposal

• Add DialogDescription (secondary sm text; ideally wired through Ark UI's Dialog.Description so aria-describedby on the dialog comes for free).
• Let DialogHeader support the stacked title + description layout without a consumer wrapper (e.g. title row keeps the close button, description renders full-width below).

Acceptance

• <DialogHeader><DialogTitle>…</DialogTitle><DialogDescription>…</DialogDescription></DialogHeader> renders title with close button on the row and description stacked under it, no consumer flex wrapper.
• Dialog root gets aria-describedby pointing at the description.

[ipwallarm]

@artem-desing Could you please implement it?
I will help you if need it.