Describe the problem

@kyrspl && @cee-chen are making a dismiss (close) button to EuiCallout in #7156. They proposed moving the heading (title) before the dismiss button in the source order so screen reader users could hear the message heading before deciding to dismiss the callout. I seconded this approach and suggested we should update EuiModal to have this same source order.

Proposed solution

! EuiFlyout lines 413-426
! https://github.com/elastic/eui/blob/main/src/components/flyout/flyout.tsx#L413C12-L426C12

<Element ...{props}>
  {!isPushed && screenReaderDescription}
! Potentially add a prop to ignore this Close button if a header exists
! Could be something like `hasHeader` that renders the button inside `EuiHeader`  {closeButton}
  {children}
</Element>

Related issues

• [EuiModal] Adjust the source order to announce EuiTitle before Close button #7222

WCAG or Vendor Guidance (optional)

• SC 1.3.2: Meaningful Sequence (Level A)

Screenshots or Trace Logs