Add Code of Conduct link to footer navigation

- Added "Code of Conduct" link to Quick Links section in footer
- Links to /code-of-conduct.html
- Improves discoverability of community guidelines

Closes #778

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Co-Authored-By: Claude <[email protected]>

Author: kjaymiller

_layouts/_includes/footer.html

@@ -16,6 +16,7 @@ <h3>Quick link</h3>
           <li><a href="/partnerships.html">Partnerships</a></li>
           <li><a href="/community.html">Community</a></li>
           <li><a href="/support.html">Support</a></li>
+          <li><a href="/code-of-conduct.html">Code of Conduct</a></li>
         </ul>
       </div>
       <!-- Contact Us Section -->