minor #823 [Demo] Polish style of sources feature of wikipedia example (chr-hertel)

This PR was merged into the main branch.

Discussion
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[Demo] Polish style of sources feature of wikipedia example

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| Docs?         | no
| Issues        |
| License       | MIT

<img width="1483" height="932" alt="image" src="https://github.com/user-attachments/assets/e7fe58e6-1c19-4ed4-87bd-2ea51e72c42f" />

Commits
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6b923ca Polish style of sources feature of wikipedia example

Author: chr-hertel

demo/templates/components/wikipedia.html.twig

@@ -9,14 +9,14 @@
     <div id="chat-body" class="card-body p-4 overflow-auto">
         {% for message in this.messages %}
             {% include '_message.html.twig' with { message, latest: loop.last } %}
-            {% if message.metadata.has('sources') %}
-                <div class="ms-5">
-                    <h6>Sources:</h6>
-                    <ol>
-                        {% for source in message.metadata.get('sources') %}
-                            <li><a class="text-black-50" href="{{ source.reference }}" target="_blank" rel="noopener">{{ source.name }}</a></li>
-                        {% endfor %}
-                    </ol>
+            {% if message.metadata.has('sources') and 0 != message.metadata.get('sources')|length %}
+                <div class="ms-5 ps-4" style="margin-top: -1.5em;">
+                    <span class="text-muted">Sources:</span>
+                    {% for source in message.metadata.get('sources') %}
+                        <a class="text-black-50" href="{{ source.reference }}" target="_blank" rel="noopener">
+                            <span class="badge text-bg-secondary">{{ source.name }}</span>
+                        </a>
+                    {% endfor %}
                 </div>
             {% endif %}
         {% else %}