docs: embed Snyk MCP demo video in cookbook

- Added YouTube video embed (https://youtu.be/cwVnKOf3tVg) to Snyk cookbook
- Positioned video after 'What You'll Build' section for immediate visibility
- Video showcases AI-powered security scanning workflows

Fixes CON-4452

Co-authored-by: Brian Douglas <nate@continue.dev>
Generated with [Continue](https://continue.dev)

Co-Authored-By: Continue <noreply@continue.dev>

Author: continue[bot]

docs/guides/snyk-mcp-continue-cookbook.mdx

@@ -10,6 +10,18 @@ sidebarTitle: "Snyk Security Scanning with Continue"
   containers - all through simple natural language prompts
 </Card>
 
+## Demo Video
+
+<iframe
+  width="100%"
+  height="400"
+  src="https://www.youtube.com/embed/cwVnKOf3tVg"
+  title="Snyk MCP Continue Cookbook Demo"
+  frameborder="0"
+  allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture"
+  allowfullscreen
+></iframe>
+
 ## Prerequisites
 
 Before starting, ensure you have: