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/Controllers/LlmsController.php

@@ -0,0 +1,120 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Blog\Controllers;
+
+use App\Models\Post;
+use Illuminate\Support\Str;
+use League\HTMLToMarkdown\HtmlConverter;
+
+class LlmsController extends Controller
+{
+    /**
+     * /llms.txt — live index for agents. Not a static file.
+     */
+    public function index()
+    {
+        $siteName = (string) blog_setting('site_name', config('blog.name'));
+        $siteDescription = (string) blog_setting('site_description', config('blog.description'));
+
+        $posts = Post::query()
+            ->published()
+            ->latest('published_at')
+            ->limit(200)
+            ->get();
+
+        $lines = [
+            '# '.$siteName,
+            '',
+            '> '.$siteDescription,
+            '',
+            '## Feeds',
+            '',
+            '- [RSS]('.route('feed.rss').')',
+            '- [Sitemap]('.route('feed.sitemap').')',
+            '- [llms.txt]('.route('feed.llms').')',
+            '',
+            '## Articles',
+            '',
+        ];
+
+        foreach ($posts as $post) {
+            if ($this->isRestricted($post)) {
+                continue;
+            }
+
+            $summary = Str::limit(trim(preg_replace('/\s+/', ' ', strip_tags($post->excerpt_or_fallback)) ?? ''), 120);
+            $markdownUrl = $this->markdownUrl($post);
+            $htmlUrl = $post->url;
+            $title = $post->title;
+
+            $lines[] = $markdownUrl
+                ? '- ['.$title.']('.$markdownUrl.') — '.$summary.' ([html]('.$htmlUrl.'))'
+                : '- ['.$title.']('.$htmlUrl.') — '.$summary;
+        }
+
+        return response(implode("\n", $lines)."\n", 200, [
+            'Content-Type' => 'text/plain; charset=utf-8',
+            'Cache-Control' => 'no-store',
+        ]);
+    }
+
+    /**
+     * /posts/{slug}.md — full markdown for a published public post.
+     */
+    public function postMarkdown(string $slug)
+    {
+        $post = Post::query()
+            ->where('slug', $slug)
+            ->orWhere('id', (int) $slug)
+            ->first();
+
+        abort_unless($post && $post->status === 'published' && ! $this->isRestricted($post), 404);
+
+        $body = $post->content_format === 'markdown'
+            ? (string) $post->content
+            : $this->htmlToMarkdown((string) $post->content);
+
+        $out = '# '.$post->title."\n\n";
+        if ($post->excerpt) {
+            $out .= '> '.$post->excerpt."\n\n";
+        }
+        $out .= $body."\n";
+
+        return response($out, 200, [
+            'Content-Type' => 'text/markdown; charset=utf-8',
+            'Cache-Control' => 'no-store',
+        ]);
+    }
+
+    private function isRestricted(Post $post): bool
+    {
+        if (filled($post->read_password)) {
+            return true;
+        }
+
+        return ! empty(($post->meta ?? [])['members_only']);
+    }
+
+    private function markdownUrl(Post $post): ?string
+    {
+        $slug = trim((string) $post->slug);
+
+        if ($slug === '') {
+            return route('geo.post.markdown', ['slug' => (string) $post->id]);
+        }
+
+        return route('geo.post.markdown', ['slug' => $slug]);
+    }
+
+    private function htmlToMarkdown(string $html): string
+    {
+        $converter = new HtmlConverter([
+            'strip_tags' => false,
+            'hard_break' => true,
+        ]);
+
+        return $converter->convert($html);
+    }
+}