fix(a11y): resolve serious accessibility issues on search page (GOO-110)

- Add aria-hidden="true" to all decorative inline SVGs (bookmark, view-mode, funnel, checkmark)
- Convert save-search popover to proper dialog: role="dialog", aria-modal, focus trap, Escape key, focus return to trigger
- Add aria-pressed on list/map/split view-mode toggle buttons
- Add aria-expanded + aria-controls on mobile filter toggle button
- Add role="status" + aria-label="Đang tải..." on Suspense fallback

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/web/components/providers/__tests__/notifications-provider.spec.tsx

@@ -0,0 +1,30 @@
+import { render, screen } from '@testing-library/react';
+import { describe, expect, it, vi } from 'vitest';
+import { NotificationsProvider } from '../notifications-provider';
+
+const useSocketNotificationsMock = vi.fn();
+
+vi.mock('@/lib/hooks/use-socket-notifications', () => ({
+  useSocketNotifications: () => useSocketNotificationsMock(),
+}));
+
+describe('NotificationsProvider', () => {
+  it('renders children', () => {
+    render(
+      <NotificationsProvider>
+        <div>child</div>
+      </NotificationsProvider>,
+    );
+    expect(screen.getByText('child')).toBeInTheDocument();
+  });
+
+  it('initializes socket notifications hook on mount', () => {
+    useSocketNotificationsMock.mockClear();
+    render(
+      <NotificationsProvider>
+        <span>x</span>
+      </NotificationsProvider>,
+    );
+    expect(useSocketNotificationsMock).toHaveBeenCalled();
+  });
+});