Preview: Block ausserhalb des Formulars, Validierung und Feinschliff

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/components/AssignedProjectCard.jsx

@@ -112,7 +112,7 @@ export default function AssignedProjectCard({ project, onUnassign, showActions =
         <StatusBadge label="Provisioning" value={project.provisioningStatus} />
       </div>
 
-      {showActions && (
+      {showActions && project.subdomain && (
         <div style={{ marginTop: 10 }}>
           <button
             type="button"
@@ -124,7 +124,7 @@ export default function AssignedProjectCard({ project, onUnassign, showActions =
           </button>
           {showPreviewBlock && (
             <div style={{ marginTop: 8 }}>
-              <PreviewBlock projectId={project.$id} />
+              <PreviewBlock key={project.$id} projectId={project.$id} />
             </div>
           )}
         </div>