Set focus to first page element on manual Snackbar close

This commit ensures that when the Snackbar component is closed manually, the focus is automatically set to the first element of the page. This improves accessibility by guiding the user's focus in a logical order, enhancing the user experience especially for keyboard and screen reader users.

Author: Hector Arce De Las Heras

src/components/snackbar/snackbarStandAlone.tsx

@@ -84,7 +84,8 @@ const SnackbarStandAloneComponent = (
       clickOverlayClose={false}
       component={PopoverComponentType.DIV}
       dataTestId={`${props.dataTestId}Popover`}
-      focusScreenFirstDescendantAfterClose={true}
+      focusLastElementFocusedAfterClose={false}
+      focusScreenFirstDescendantAfterClose={false}
       open={props.open}
       pressEscapeClose={false}
       variant={props.styles?.popoverVariants?.[align]}

src/components/snackbar/snackbarUnControlled.tsx

@@ -1,5 +1,7 @@
 import * as React from 'react';
 
+import { focusFirstDescendant } from '@/utils';
+
 import { SnackbarControlled } from './snackbarControlled';
 import { ISnackbarUnControlled } from './types';
 
@@ -53,6 +55,8 @@ const SnackbarUnControlledComponent = <V extends string | unknown>(
   const handleCloseButton: (_open: boolean) => React.MouseEventHandler<HTMLButtonElement> =
     _open => event => {
       props.onOpenClose?.(_open, event);
+      // Only after the user closes the snackbar manually, the focus will be set to the first focusable element of the page
+      focusFirstDescendant(document.body);
     };
 
   const handleMouseEnter = (event: React.MouseEvent<HTMLDivElement>) => {