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>

themes/demo/views/partials/footer.blade.php

@@ -1,6 +1,7 @@
 <footer class="d-footer">
     <div class="d-container">
         <p>© {{ date('Y') }} {{ $siteName }}@if($siteIcp) · <a href="https://beian.miit.gov.cn/" target="_blank" rel="noopener">{{ $siteIcp }}</a>@endif</p>
+        <p>@include('partials.feed-links')</p>
         <p>由 LaraLog 驱动 · Demo 主题</p>
     </div>
 </footer>

themes/demo/views/partials/head.blade.php

@@ -11,6 +11,7 @@
     <meta name="generator" content="LaraLog">
     <link rel="canonical" href="{{ url()->current() }}">
     <link rel="alternate" type="application/rss+xml" title="{{ $siteName }}" href="{{ route('feed.rss') }}">
+    <link rel="alternate" type="text/plain" title="llms.txt" href="{{ route('feed.llms') }}">
     {{-- 主题资产：/themes/demo/assets/style.css --}}
     <link rel="stylesheet" href="{{ theme('asset', 'style.css') }}">
     @stack('head')

themes/demo/views/partials/header.blade.php

@@ -6,6 +6,7 @@
             <a href="{{ route('archives') }}" class="{{ request()->routeIs('archives*') ? 'active' : '' }}">归档</a>
             <a href="{{ route('tags') }}" class="{{ request()->routeIs('tags*') ? 'active' : '' }}">标签</a>
             <a href="{{ route('links') }}" class="{{ request()->routeIs('links') ? 'active' : '' }}">友链</a>
+            @include('partials.feed-links')
             <form class="d-search" action="{{ route('search') }}" method="get">
                 <input type="search" name="q" placeholder="搜索..." value="{{ request('q', request('keyword', '')) }}">
             </form>