fix: code blocks rendering + consistent styling with ciphera-website /learn

- Convert MDX CodeBlock components to standard markdown code fences
- Add rehype-mdx-code-props to pass filename meta to code components
- Custom pre/code MDX components map fences to CodeBlock
- Add brand color badges (product + category) matching /learn layout
- Match prose styling: orange inline code, orange links, white strong
- Remove brand color background glow (not in /learn)

content/integrations/squarespace.mdx

@@ -16,11 +16,13 @@ Use Squarespace's Code Injection feature to add the Pulse script.
 
 Go to **Settings -> Developer Tools -> Code Injection -> Header** and paste the Pulse script.
 
-<CodeBlock filename="Settings -> Code Injection -> Header">{`<script
+```html filename="Settings -> Code Injection -> Header"
+<script
   defer
   data-domain="your-site.com"
   src="https://pulse.ciphera.net/script.js"
-></script>`}</CodeBlock>
+></script>
+```
 
 **Note:** Code Injection requires a Business or Commerce plan.