Fix bug in UserManagement.tsx

Author: gnmyt

client/src/components/admin/UserManagement.tsx

@@ -177,7 +177,7 @@ export const UserManagement = () => {
                                             </Badge>
                                         </TableCell>
                                         <TableCell>
-                                            {new Date(userData.created_at).toLocaleDateString()}
+                                            {userData.created_at ? new Date(userData.created_at).toLocaleDateString() : 'N/A'}
                                         </TableCell>
                                         <TableCell>
                                             <Button

client/src/types/index.ts

@@ -8,6 +8,7 @@ export interface User {
     oauth_id?: string;
     profile_picture?: string | null;
     is_project_member?: boolean;
+    created_at?: string;
 }
 
 export interface Project {