Fix page parity: images on even (left) pages, text on odd (right) pages

Add a section-title page ("Die Geschichten") as page 3 so all stories
begin on page 4. Image and text for each scene now land on the same
facing spread (even=left image, odd=right text). Page count: 99 → 100.

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

templates/book.html

@@ -28,6 +28,15 @@
     </ol>
   </div>
 
+  {# ── Section title — keeps stories starting on an even (left) page ── #}
+  <div class="page page--section">
+    <div class="section-title-inner">
+      <span class="section-ornament">❧</span>
+      <h2 class="section-title">Die Geschichten</h2>
+      <span class="section-rule"></span>
+    </div>
+  </div>
+
   {# ── Stories ── #}
   {% for story in stories %}
     {% include "story-spread.html" %}