[BUG] ZCode 3.10.1 (Linux AppImage): WeChat bot processes messages but outbound replies never reach WeChat (Silent failure)

Bug Description

On ZCode 3.10.1 (Linux AppImage on Ubuntu 26.04), the WeChat (weixin) bot integration receives inbound messages and completes agent response generation in the bound workspace, but outbound replies are never delivered back to WeChat (silent failure, no error displayed or logged).

Environment Details

• ZCode Version: 3.10.1 (Linux AppImage)
• OS: Ubuntu 26.04 (Linux x64)
• Model / Plan: GLM Coding Plan (GLM-5.3)
• Bot Mode: WeChat Bot (provider=weixin), long-polling mode, reply = Standard
• Original Discord Report: Discord Thread #1543655721080721469
• User Reference: Jiamo.im (@Jiamo.im) & @Roman | Z (Volunteer/Mod)
• Related Issue: Related to #200 (outbound iLink delivery failure)

Reproduction Steps

1. Bind WeChat via QR code on ZCode 3.10.1 AppImage (status shows "long-polling running").
2. Send any text message from WeChat to the bot (e.g. 测试 / test or /status).
3. Actual Result:
   • WeChat shows "typing…" for a few seconds, then stops — no reply ever arrives.
   • On Desktop ZCode GUI, the message is fully processed: workspace task created, agent response generated (snapshot completed, contentChars: 161).
   • Outbound delivery to WeChat is silently dropped with zero error logs.
4. Expected Result: The generated agent reply should be delivered back to the WeChat user.

Log Evidence (~/.zcode/v2/logs/2026-08-31.log)

00:54:39 [bots] provider callback provider=weixin ... text=测试 ("test") ← received
00:54:40 [zcode-task-service] sendPrompt started ← dispatched into a task
00:54:58 snapshot {assistantMessages:3, contentChars:161, completed} ← reply generated
(no reply-send log line, no error, nothing after this)

CLI Log Inspection (~/.zcode/cli/log/*.jsonl)

• Zero bot-related entries — the reply send handler never executes locally after the task completion event.

Troubleshooting Attempted (All Failed):

• Full GUI & system tray restart.
• Removed stale webRemoteControlExternalRelayDevice bindings (drop warnings resolved, but replies still lost).
• Rebound bot session workspace.
• Deleted bot + re-scanned QR code (new cloud bot account 704136178063@im.bot, fresh credentials, identical failure).

Root Cause Analysis

The inbound message pipeline ([bots] provider callback → zcode-task-service) works as expected, but the outbound IPC event bridge in ZCode v3.10.1 Linux AppImage fails to trigger the weixin provider client outbound send callback when zcode-task-service completes the task snapshot.

Start with the reproduction steps and inspect ~/.zcode/v2/logs/2026-08-31.log, following the provider callback, zcode-task-service completion, and missing reply-send event. Compare the working inbound path with the outbound IPC bridge for the weixin provider; done means the generated reply reaches WeChat and the send path produces the expected log entry.