feat: restore sablog browse modes and clean imported HTML

Keep the public site readable after import (nbsp, highlighter, wrapping code, compact pager) and finish the admin extras already in this tree: sticky levels, preview, page cache, and live llms.txt.

Co-authored-by: Cursor <cursoragent@cursor.com>

resources/views/filament/hooks/topbar-tools.blade.php

@@ -9,6 +9,18 @@
         {{ $environmentName }}
     </x-filament::badge>
 
+    <x-filament::button
+        tag="a"
+        href="{{ url('/') }}"
+        target="_blank"
+        rel="noopener noreferrer"
+        size="sm"
+        color="gray"
+        icon="heroicon-o-globe-alt"
+    >
+        网站
+    </x-filament::button>
+
     <x-filament::button
         tag="a"
         :href="$createPostUrl"