fix: variables als Objekt statt Array crasht Email Templates

Backend gibt variables manchmal als {} (Objekt) statt [] (Array)
zurueck. (template.variables || []).map() greift nicht weil {}
truthy ist. Fix: Array.isArray() Check in TemplateCard + EditorTab.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

admin-compliance/app/sdk/email-templates/_components/TemplateCard.tsx

@@ -30,12 +30,12 @@ export function TemplateCard({ template, onEdit }: TemplateCardProps) {
         <p className="text-xs text-gray-500 mt-2 line-clamp-2">{template.description}</p>
       )}
       <div className="mt-3 flex flex-wrap gap-1">
-        {(template.variables || []).slice(0, 4).map(v => (
+        {(Array.isArray(template.variables) ? template.variables : []).slice(0, 4).map(v => (
           <span key={v} className="px-1.5 py-0.5 bg-gray-50 text-gray-500 rounded text-xs font-mono">
             {`{{${v}}}`}
           </span>
         ))}
-        {(template.variables || []).length > 4 && (
+        {Array.isArray(template.variables) && template.variables.length > 4 && (
           <span className="text-xs text-gray-400">+{template.variables.length - 4}</span>
         )}
       </div>