- Persist conversationScene in create/update conversation
- Make bindAccount validate by conversation scene (1=WECOM_BOT, 2=WECHAT_PERSONAL)
- Re-derive channelType from conversation_scene in dispatchRecord
- Check WeCom response errcode and HTTP status in WeComBotSender
- Support custom webhook_url from ext_info in WeComBotSender
- Configure RestTemplate with 5s connect / 10s read timeouts
- Expand WeComBotSenderTest with MockRestServiceServer coverage