Add the bootstrap theme

FIXME: external imports might get out of hand at scale
FIXME: I didn't version the version of bootstrap so scaling will
definitely make things break eventually

app/views/layouts/application.html.erb

@@ -7,6 +7,7 @@
     <%= csp_meta_tag %>
 
     <%= stylesheet_link_tag "application", "data-turbo-track": "reload" %>
+    <%= stylesheet_link_tag "application", "https://cdn.jsdelivr.net/npm/bootstrap/dist/css/bootstrap.min.css" %>
     <%= javascript_importmap_tags %>
   </head>