Add Discord link to footer

A new Discord link has been added to the footer navigation for improved community access.

Author: SableRaf

src/components/Footer.js

@@ -22,6 +22,9 @@ const Footer = ({ withSidebar }) => {
           <li>
             <a href={'http://github.com/processing/'} target="_blank" rel="noreferrer">GitHub</a>
           </li>
+          <li>
+            <a href={'https://discord.gg/aWTgcaGdjr'} target="_blank" rel="noreferrer">Discord</a>
+          </li>
           <li>
             <a href={'https://bsky.app/profile/processing.org'} target="_blank" rel="noreferrer">Bluesky</a>
           </li>