feat: add the booking board with floor plan and calendar

templates/dashboard/index.html.twig

@@ -3,6 +3,29 @@
 {% block title %}Übersicht · ephub{% endblock %}
 
 {% block content %}
-    <h1>Übersicht</h1>
-    <p class="subline">Schreibtische und Parkplätze buchen.</p>
+    <h1>Buchen</h1>
+    <p class="subline">Tag im Kalender wählen, dann einen freien Platz im Raumplan anklicken.</p>
+
+    <div class="mt-8 grid gap-8 xl:grid-cols-3">
+        <div class="xl:col-span-1">
+            {#
+                The two blocks below are what DashboardController::day and BookingController
+                swap out of band. Each one owns a stable id and emits hx-swap-oob only when
+                rendered through htmxOobResponse -- rendered normally they are plain markup.
+            #}
+            {% block calendar %}
+                <div id="board-calendar"{% if htmx_oob_swap is defined and htmx_oob_swap %} hx-swap-oob="true"{% endif %}>
+                    {% include 'dashboard/_calendar.html.twig' %}
+                </div>
+            {% endblock %}
+        </div>
+
+        <div class="xl:col-span-2">
+            {% block floorplan %}
+                <div id="board-floorplan"{% if htmx_oob_swap is defined and htmx_oob_swap %} hx-swap-oob="true"{% endif %}>
+                    {% include 'dashboard/_floorplan.html.twig' %}
+                </div>
+            {% endblock %}
+        </div>
+    </div>
 {% endblock %}