Add new story for darkmode (#317)

* Add a new story for dark mode

* Reorganize storybook menu

* Fix command menu margins

* Fix tests

front/.storybook/preview.ts

@@ -4,7 +4,6 @@ import { ThemeProvider } from '@emotion/react';
 import { withThemeFromJSXProvider } from "@storybook/addon-styling";
 import { lightTheme, darkTheme } from '../src/modules/ui/layout/styles/themes';
 
-
 initialize();
 
 const preview: Preview = {