WeChat Work Robot API mode with WebSocket for proactive messaging

[longzhi]

Background

WeCom (企业微信) version 5.0.7 introduced a new Robot API mode with WebSocket long connections that supports:

• WebSocket-based persistent connection (no public domain/IP required)
• Proactive message sending (the current AI Bot mode cannot do this)
• Document/spreadsheet editing authorization for bot members
• Event reminders

Current State

The existing wecom.rs channel adapter uses the AI Bot mode (aibot_subscribe / aibot_respond_msg / aibot_msg_callback), which is a request-response protocol. It cannot send proactive messages, which means:

• Scheduled task delivery is not supported
• Approval UI cannot be pushed to users (currently warn-only with 60s timeout fallback)
• Announcements cannot be delivered proactively

Proposal

Implement a new WeCom channel adapter (or extend the existing one) using the Robot API mode WebSocket protocol. This would enable:

1. Approval UI — push interactive approval requests (text-based /approve commands) to the conversation when the agent needs filesystem access
2. Scheduled task delivery — deliver scheduled task results proactively
3. Announcement delivery — support DeliverAnnounce bus events

References

• WeCom 5.0.7 release notes (2026-03-14)
• Current implementation: crates/clawhive-channels/src/wecom.rs
• Approval pattern reference: crates/clawhive-channels/src/dingtalk.rs (similar WebSocket + proactive send)