feat: Add OwnerList component for displaying and managing team owner accounts with pagination and filtering.

frontend/src/components/upload/OwnerList.tsx

@@ -159,7 +159,9 @@ export default function OwnerList() {
                                 owners.map((owner) => (
                                     <tr key={owner.id} className="border-t border-slate-100 dark:border-slate-800 hover:bg-slate-50 dark:hover:bg-slate-800/50">
                                         <td className="p-3 text-slate-900 dark:text-slate-100">{owner.email}</td>
-                                        <td className="p-3 font-mono text-xs text-slate-500">{owner.account_id?.slice(0, 20)}...</td>
+                                        <td className="p-3 font-mono text-xs text-slate-500">
+                                            {owner.account_id ? `${owner.account_id.slice(0, 20)}...` : '-'}
+                                        </td>
                                         <td className="p-3">
                                             <span className={`px-2 py-0.5 rounded-full text-xs ${statusColors[owner.status] || 'bg-slate-100 text-slate-700'}`}>
                                                 {statusLabels[owner.status] || owner.status}