Implement basic login function; add basic styling

src/Middlewares.php

@@ -3,6 +3,7 @@ declare(strict_types=1);
 
 namespace MailAccountAdmin;
 
+use MailAccountAdmin\Auth\AuthMiddleware;
 use Slim\App;
 use Slim\Views\TwigMiddleware;
 
@@ -13,6 +14,7 @@ class Middlewares
         $displayErrorDetails = $settings->isDebugMode();
 
         $app->addErrorMiddleware($displayErrorDetails, true, true);
+        $app->add(new AuthMiddleware());
         $app->add(TwigMiddleware::createFromContainer($app));
     }
 }