[TASK] Render icon identifier for easy copy

Author: o-ba

tmpl/html/docs/single.html.twig

@@ -159,6 +159,9 @@
     <div class="section">
         <h2 class="mb-3">Usage</h2>
 
+        <h3 class="my-3">Icon Identifier</h3>
+        {{ makros.codeblock(icon.identifier) }}
+
         <h3 class="my-3">Markup</h3>
         {{ makros.codeblock(icon._inline, 'svg') }}