Keep the snackbar's live region in the page

The region carrying aria-live was created together with its message, inside the
x-if that draws the snackbar, so a screen reader had nothing to notice changing.
It moves to the permanent host, which is polite and atomic as M3 asks; a type
now only picks the region's role, and the explicit aria-live keeps an error
polite too. Plan step 11, actions.md ACT-02.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9

tests/Feature/Components/ToastTest.php

@@ -18,6 +18,16 @@ it('marks the snackbar and its action for tests and styling', function () {
     $html = (string) $this->blade('<x-toast />');
 
     expect($html)
-        ->toMatch('/<div\s[^>]*\bdata-toast\b[^>]*aria-live="polite"/')
+        ->toMatch('/<div\s[^>]*\bdata-toast\b/')
         ->toMatch('/<button\s[^>]*\bdata-toast-action\b[^>]*x-on:click="act\(\)"/');
 });
+
+it('keeps the live region in the page, polite, around the snackbar that comes and goes', function () {
+    $html = (string) $this->blade('<x-toast />');
+
+    expect($html)
+        ->toMatch('/<div\s[^>]*x-data="materialSnackbar"[^>]*aria-live="polite"/')
+        ->toContain('aria-atomic="true"')
+        ->toContain("x-bind:role=\"current && (current.type === 'error' || current.type === 'warning') ? 'alert' : 'status'\"")
+        ->and(substr_count($html, 'aria-live'))->toBe(1);
+});