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>

app/Blog/Services/PostContentRenderer.php

@@ -6,6 +6,7 @@ declare(strict_types=1);
 namespace App\Blog\Services;
 
 use App\Blog\Support\MarkdownMediaEmbed;
+use App\Blog\Support\SablogHtmlNormalizer;
 use App\Models\Post;
 use Illuminate\Support\Facades\Cache;
 use League\CommonMark\Environment\Environment;
@@ -38,7 +39,7 @@ class PostContentRenderer
     public function render(Post $post): string
     {
         $embed = app(MarkdownMediaEmbed::class);
-        $raw = (string) $post->content;
+        $raw = app(SablogHtmlNormalizer::class)->normalize((string) $post->content);
 
         $content = $post->content_format === 'markdown'
             ? $this->toHtml($embed->expandMarkdown($raw))