feat: add the booking board with floor plan and calendar

templates/layout.html.twig

@@ -39,5 +39,11 @@
         </div>
     </div>
 
-    {% include '_partials/_flashes.html.twig' %}
+    {# Swapped out of band after a booking, hence the stable id and the conditional attribute. #}
+    {% block flashes %}
+        <div id="flashes" class="fixed bottom-4 right-4 z-50 space-y-2"
+             {%- if htmx_oob_swap is defined and htmx_oob_swap %} hx-swap-oob="true"{% endif %}>
+            {% include '_partials/_flashes.html.twig' %}
+        </div>
+    {% endblock %}
 {% endblock %}