feat: record who created join codes and who added each node [CI]

web/admin/src/pages/Agents.tsx

@@ -195,6 +195,7 @@ export function Agents() {
               <thead>
                 <tr>
                   <th>备注</th>
+                  <th>创建者</th>
                   <th>使用</th>
                   <th>注册后</th>
                   <th>过期</th>
@@ -209,6 +210,7 @@ export function Agents() {
                   return (
                     <tr key={t.id}>
                       <td>{t.note || <span className="faint">—</span>}</td>
+                      <td className="muted">{t.created_by ?? '—'}</td>
                       <td className="num">
                         {t.uses} / {t.max_uses}
                       </td>