Growth features: share buttons, NEW badge, sticky CTA, newsletter cross-promote

- Share buttons on episode and clip cards (Web Share API + clipboard fallback)
- NEW badge on latest episode card
- Sticky call-in CTA bar (appears after hero scrolls out)
- Daily AI Briefing newsletter cross-promote in footer
- Bump cache versions to v=5

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

website/js/clips.js

@@ -1,6 +1,7 @@
 const CLIPS_JSON_URL = '/data/clips.json';
 
 const clipPlaySVG = '<svg viewBox="0 0 24 24" fill="#fff"><path d="M8 5v14l11-7z"/></svg>';
+const clipShareSVG = '<svg viewBox="0 0 24 24" fill="#fff"><path d="M16 5l-1.42 1.42-1.59-1.59V16h-2V4.83L9.42 6.42 8 5l4-4 4 4zm4 5v11a2 2 0 01-2 2H6a2 2 0 01-2-2V10a2 2 0 012-2h3v2H6v11h12V10h-3V8h3a2 2 0 012 2z"/></svg>';
 
 function escapeHTML(str) {
   const el = document.createElement('span');
@@ -8,6 +9,26 @@ function escapeHTML(str) {
   return el.innerHTML;
 }
 
+async function shareClipContent(title, url, btn) {
+  if (navigator.share) {
+    try {
+      await navigator.share({ title, url });
+      return;
+    } catch (e) {
+      if (e.name === 'AbortError') return;
+    }
+  }
+  try {
+    await navigator.clipboard.writeText(url);
+    const orig = btn.innerHTML;
+    btn.innerHTML = 'Copied!';
+    btn.classList.add('share-copied');
+    setTimeout(() => { btn.innerHTML = orig; btn.classList.remove('share-copied'); }, 2000);
+  } catch (e) {
+    prompt('Copy this link:', url);
+  }
+}
+
 function renderClipCard(clip, featured) {
   const card = document.createElement('div');
   card.className = 'clip-card' + (featured ? ' clip-card-featured' : '');
@@ -31,6 +52,7 @@ function renderClipCard(clip, featured) {
         <h3 class="clip-card-title">${title}</h3>
         <p class="clip-card-desc">${desc}</p>
         ${hasVideo ? `<button class="clip-play-btn" aria-label="Play clip">${clipPlaySVG}</button>` : ''}
+        ${hasVideo ? `<button class="clip-share-btn" aria-label="Share clip">${clipShareSVG}</button>` : ''}
       </div>
     </div>
   `;
@@ -41,6 +63,13 @@ function renderClipCard(clip, featured) {
       const inner = card.querySelector('.clip-card-inner');
       inner.innerHTML = `<iframe src="https://www.youtube-nocookie.com/embed/${youtubeId}?autoplay=1&rel=0" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>`;
     });
+    const shareBtn = card.querySelector('.clip-share-btn');
+    if (shareBtn) {
+      shareBtn.addEventListener('click', (e) => {
+        e.stopPropagation();
+        shareClipContent(clip.title || '', `https://youtube.com/watch?v=${youtubeId}`, shareBtn);
+      });
+    }
   }
 
   return card;