feat(slides): add demo video placeholder to showcase live functionality

Author: alfarahn

.gitignore

@@ -89,3 +89,4 @@ secrets.json
 # Local Dragon's Den / pitch prep notes
 docs/local/
 .github/agents/competition.agent.md
+.github/agents/triage.agent.md

src/Dashboard/frontend/public/slides.html

@@ -3478,6 +3478,65 @@ <h3>Own it.</h3>
         </div>
       </section>
 
+      <!-- ========== Slide 5a: Demo video placeholder ========== -->
+      <section class="slide s5a">
+        <div class="content">
+          <h2 class="section-title anim d1">See it <em>live</em>.</h2>
+          <p class="section-lead anim d2">
+            Score → Auto-fix → Re-score on real Azure data — under 3 minutes.
+          </p>
+          <div
+            class="video-frame anim d3"
+            style="
+              position: relative;
+              width: 100%;
+              max-width: 1400px;
+              margin: 1.5rem auto 0;
+              padding-top: 56.25%;
+              border-radius: 16px;
+              overflow: hidden;
+              background: #0a1733;
+              box-shadow: 0 20px 60px rgba(10, 23, 51, 0.25);
+              border: 1px solid var(--line);
+            "
+          >
+            <!-- Replace src with your demo video URL (YouTube embed or MP4) -->
+            <div
+              style="
+                position: absolute;
+                inset: 0;
+                display: flex;
+                align-items: center;
+                justify-content: center;
+                color: rgba(255, 255, 255, 0.55);
+                font-size: 1.2rem;
+                font-weight: 600;
+                letter-spacing: 0.04em;
+                text-align: center;
+                padding: 2rem;
+                line-height: 1.5;
+              "
+            >
+              ▶ Demo video goes here<br />
+              <span style="font-size: 0.85rem; font-weight: 400; opacity: 0.7"
+                >Replace this div with an &lt;iframe&gt; or &lt;video&gt;
+                element</span
+              >
+            </div>
+            <!--
+              <iframe
+                src="https://www.youtube.com/embed/YOUR_VIDEO_ID?rel=0&modestbranding=1&playsinline=1&controls=1"
+                title="Azure FinOps Agent · live demo"
+                loading="lazy"
+                allow="autoplay; encrypted-media; fullscreen; picture-in-picture"
+                allowfullscreen
+                style="position:absolute;inset:0;width:100%;height:100%;border:0"
+              ></iframe>
+            -->
+          </div>
+        </div>
+      </section>
+
       <!-- ========== Slide 5b: Proof ========== -->
       <section class="slide s5b">
         <div class="content">