Fix #67: Update hero CTA and speaking page reel placeholder

- Change homepage hero CTA from 'Watch the Reel' to 'Explore Speaking'
- Update speaking page reel placeholder to acknowledge missing video
- Add direction to signature talks below the reel placeholder

#50 and #47 already resolved in codebase:
- Hero images exist in public/images/
- Favicon exists (favicon.ico and favicon.svg)
- Manifest.json exists

src/pages/speaking.astro

@@ -28,7 +28,7 @@ import SharedForm from '../components/Form/SharedForm.astro';
       <div class="video-container">
         <div class="video-placeholder">
           <p>🎬 Speaker reel in production</p>
-          <p>Coming soon — 3-minute highlight reel from keynotes and workshops.</p>
+          <p>Coming soon — 3-minute highlight reel from keynotes and workshops. In the meantime, explore my signature talks below.</p>
         </div>
       </div>
     </div>