use bootstrap 5 for UI, compact UI

internal/dashboard/templates/overview.html

@@ -4,7 +4,7 @@
 <head>{{template "html_head" .}}</head>
 <body>
 {{template "page_header" .}}
-<main>
+<main class="container-fluid py-3">
 <div id="error-banner">{{template "banner_inner" .Banner}}</div>
 {{template "overview_content" .}}
 </main>