fix: 向导设备信息不再依赖Online标志，直接查询agent

internal/web/ui.go

@@ -1491,15 +1491,12 @@ func (u *UI) apiWizardDeviceInfo(w http.ResponseWriter, r *http.Request) {
         "name":      dev.DisplayName(),
     }
 
-    if u.agent != nil && dev.Online {
-        // Channels: use management DB for friendly names and RTSP URLs
+    if u.agent != nil {
+        // Always attempt to query agent - Online flag may be stale
         channels := queryDeviceChannelsFromDB(u.preview, deviceID)
         resp["channels"] = channels
-
         caps := queryAgentCapabilities(u.agent, dev)
         resp["capabilities"] = caps
-
-        // Include currently enabled features from management DB
         if u.preview != nil {
             if enabled, err := u.preview.GetDeviceFeatures(deviceID); err == nil {
                 resp["enabled_features"] = enabled