Remove sassmeister.com support due to service closure

The sassmeister.com Sass playground service is no longer accessible (DNS resolution failure). This commit removes the adapter, related code, and test files.

Changes:
- Remove Sassmeister adapter from ExtractorFactory
- Delete Sassmeister adapter directory (Extractor and Code detector)
- Remove testSassmeister() from PagesTest
- Delete cached responses and test fixtures

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: uzulla

src/Adapters/Sassmeister/Detectors/Code.php

@@ -24,7 +24,6 @@ class ExtractorFactory
         'github.com' => Adapters\Github\Extractor::class,
         'wikipedia.org' => Adapters\Wikipedia\Extractor::class,
         'archive.org' => Adapters\Archive\Extractor::class,
-        'sassmeister.com' => Adapters\Sassmeister\Extractor::class,
         'facebook.com' => Adapters\Facebook\Extractor::class,
         'instagram.com' => Adapters\Instagram\Extractor::class,
         'imageshack.com' => Adapters\ImageShack\Extractor::class,

src/Adapters/Sassmeister/Extractor.php

@@ -84,11 +84,6 @@ public function testSnipplr()
         $this->assertEmbed('http://snipplr.com/view/72914/better-html-5-basic-starter-template');
     }
 
-    public function testSassmeister()
-    {
-        $this->assertEmbed('http://sassmeister.com/gist/1122e441f0434ec6eb2a');
-    }
-
     public function testImageShack()
     {
         $this->assertEmbed('https://imageshack.com/i/ip7wO0v7j');