Adiciona barra social lateral ao tema do microsite

Implementa o layout estilo Olivero: em desktop (≥ 1200 px) a região
Social fica fixada à esquerda com conteúdo girado −90°; em mobile exibe
barra horizontal compacta. Usa IntersectionObserver para aplicar
.is-fixed ao scroll.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

themes/site_users_microsite_theme/templates/layout/region--social.html.twig

@@ -0,0 +1,20 @@
+{#
+/**
+ * @file
+ * Template para a região Social — barra lateral vertical (estilo Olivero).
+ *
+ * Available variables:
+ * - content: The content for this region, typically blocks.
+ * - attributes: HTML attributes for the region <div>.
+ * - region: The name of the region variable as defined in the theme's
+ *   .info.yml file.
+ *
+ * @see \Drupal\Core\Theme\ThemePreprocess::preprocessRegion()
+ */
+#}
+
+<div class="social-bar__inner" data-drupal-selector="social-bar-inner">
+  <div class="rotate">
+    {{ content }}
+  </div>
+</div>