Add slide 8: configuration drift, reproducibility, scaling

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

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@@ -102,6 +102,12 @@
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   </section>
 
+  <!-- ─── SLIDE 8 ──────────────────────────────────────────────────── -->
+  <section>
+    <h2>Configuration drift is silent… until it isn't.</h2>
+    <p><em>Prod breaks on a Tuesday. You can't reproduce the bug locally. You can't scale reliably. You can't onboard a new server without fear.</em></p>
+  </section>
+
 
 </div>
 </div>