fix(channels): memory leaks, race conditions, and stability fixes

[jdmanring]

Summary

Multiple stability fixes across channel implementations (weixin, qqbot, feishu, telegram, dingtalk):

• C-02: Added TTL-based eviction to weixin channel Maps to prevent unbounded memory growth
• C-03: Replaced private SessionRouter internals access in qqbot with public API
• C-10, C-11: Fixed dual-emit of approval_mode_changed events and feishu busy-wait race condition
• H-10-H-18: Fixed memory leaks, reconnect loops, double-read bugs, and WS probe race conditions
• L-24-L-27: Fixed stripTables multiline cells, redacted telegram token in logs, stricter isTableRow, countFences regex

Files Changed

• packages/channels/weixin/src/monitor.ts
• packages/channels/weixin/src/WeixinAdapter.ts
• packages/channels/qqbot/src/QQChannel.ts
• packages/channels/feishu/src/FeishuAdapter.ts
• packages/acp-bridge/src/bridge.ts

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature
• Breaking change
• Refactor

Testing

• Unit tests pass
• Integration tests pass
• Manual testing performed