web: unify Agent management and add a draggable link board

Replace Probe pages with directed Agent links, shared deployment controls and unified display data. Add node dragging, canvas pan and zoom, saved layouts, and per-direction link controls.

web/admin/src/pages/Agents.tsx

@@ -30,7 +30,7 @@ function AddAgentDialog({ onClose, onCreated }: { onClose: () => void; onCreated
   const [created, setCreated] = useState<CreatedJoinTokenDto>()
   const [controllers, setControllers] = useState<string[] | null>(null)
 
-  if (created) return <JoinTokenCreated created={created} kind="Agent" onClose={onClose} />
+  if (created) return <JoinTokenCreated created={created} onClose={onClose} />
 
   return (
     <Dialog
@@ -151,7 +151,7 @@ export function Agents() {
                   <th>名称</th>
                   <th>地址</th>
                   <th>版本</th>
-                  <th>连着的 Probe</th>
+                  <th>连接（拨出 / 接入）</th>
                   <th>最后在线</th>
                   <th>标签</th>
                 </tr>
@@ -171,7 +171,7 @@ export function Agents() {
                     <td className="mono muted">{a.public_host || '—'}</td>
                     <td className="muted">{a.agent_version ?? '—'}</td>
                     <td>
-                      <Chip tone={a.probes.length > 0 ? 'ok' : ''}>{a.probes.length} 个</Chip>
+                      <Chip tone={a.outgoing.length + a.dialers.length > 0 ? 'ok' : ''}>{a.outgoing.length} / {a.dialers.length}</Chip>
                     </td>
                     <td className="muted">{fmtAgo(a.last_seen_at)}</td>
                     <td>