Username and username link integrity check

ts/components/LeftPaneBanner.stories.tsx

@@ -0,0 +1,25 @@
+// Copyright 2023 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import React from 'react';
+import { action } from '@storybook/addon-actions';
+import type { Meta } from '@storybook/react';
+import { LeftPaneBanner, type PropsType } from './LeftPaneBanner';
+
+export default {
+  title: 'Components/LeftPaneBanner',
+  component: LeftPaneBanner,
+  argTypes: {
+    actionText: { control: { type: 'string' } },
+    children: { control: { type: 'string' } },
+  },
+  args: {
+    actionText: 'Fix now',
+    children: 'Recoverable issue detected',
+    onClick: action('onClick'),
+  },
+} satisfies Meta<PropsType>;
+
+export function Defaults(args: PropsType): JSX.Element {
+  return <LeftPaneBanner {...args} />;
+}