feat: PlatformChannel 支持 AdapterID/AdapterName — 多账号全链路区分

- PlatformChannel 新增 AdapterID + AdapterName 字段
- AddOrUpdatePlatformChannel 接受 adapter 信息参数
- channel_sync 传递 adapter_id/adapter_name
- 消息处理路径传递 adapter_name

Co-Authored-By: Claude <noreply@anthropic.com>

backend/ai-core/cmd/channel_sync.go

@@ -48,6 +48,8 @@ func doSync(thinker *background.Thinker, client *http.Client, baseURL, token str
 			ChannelType string `json:"channel_type"`
 			ChannelID   string `json:"channel_id"`
 			ChannelName string `json:"channel_name,omitempty"`
+			AdapterID   string `json:"adapter_id,omitempty"`
+			AdapterName string `json:"adapter_name,omitempty"`
 		} `json:"channels"`
 	}
 	if err := json.NewDecoder(resp.Body).Decode(&result); err != nil {
@@ -56,7 +58,7 @@ func doSync(thinker *background.Thinker, client *http.Client, baseURL, token str
 	}
 
 	for _, ch := range result.Channels {
-		thinker.AddOrUpdatePlatformChannel(ch.Platform, ch.ChannelType, ch.ChannelID, ch.ChannelName)
+		thinker.AddOrUpdatePlatformChannel(ch.Platform, ch.ChannelType, ch.ChannelID, ch.ChannelName, ch.AdapterID, ch.AdapterName)
 	}
 
 	// Also fetch platforms to get bot UIDs.