Add a backup media download progress bar

ts/components/BackupMediaDownloadProgress.stories.tsx

@@ -0,0 +1,27 @@
+// Copyright 2024 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import React, { type ComponentProps } from 'react';
+import type { Meta, StoryFn } from '@storybook/react';
+import { setupI18n } from '../util/setupI18n';
+import enMessages from '../../_locales/en/messages.json';
+import { BackupMediaDownloadProgressBanner } from './BackupMediaDownloadProgress';
+
+const i18n = setupI18n('en', enMessages);
+
+type PropsType = ComponentProps<typeof BackupMediaDownloadProgressBanner>;
+
+export default {
+  title: 'Components/BackupMediaDownloadProgress',
+} satisfies Meta<PropsType>;
+
+// eslint-disable-next-line react/function-component-definition
+const Template: StoryFn<PropsType> = (args: PropsType) => (
+  <BackupMediaDownloadProgressBanner {...args} i18n={i18n} />
+);
+
+export const InProgress = Template.bind({});
+InProgress.args = {
+  downloadedBytes: 92048023,
+  totalBytes: 1024102532,
+};