Add banner, Apple Podcasts link, feed proxy, and fetch retry

- Add roostbanner.png hero banner image
- Add Apple Podcasts subscribe button
- Add Cloudflare Pages Function to proxy RSS feed (avoids CORS)
- Add fetch timeout and retry for episode loading
- Add contact email to footer
- Replace favicon with inline SVG rooster

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

functions/feed.js

@@ -0,0 +1,12 @@
+export async function onRequest() {
+  const feedUrl = 'https://podcast.macneilmediagroup.com/@LukeAtTheRoost/feed.xml';
+  const res = await fetch(feedUrl);
+  const xml = await res.text();
+  return new Response(xml, {
+    headers: {
+      'Content-Type': 'application/xml',
+      'Access-Control-Allow-Origin': '*',
+      'Cache-Control': 'public, max-age=300',
+    },
+  });
+}