backthink 决策+路由(P2)就绪但无投递 sink(ActiveClient/IMAdapter 无实现)。补齐: - gateway/proactive.go: hub.SendProactive 向 owner/admin 连接广播 proactive_message WS事件, 内容脱敏(去RawData/media/token),返回接收数,count=0→IM兜底;Server.SendProactive 委托 - channelbridge/proactive.go: Bridge.SendProactive 解析 owner 账户(msg.Platform→匹配白名单账号, 否则首个已配置主人频道),ChannelType=Direct+ChannelID/SenderID=owner id,走 adapter.SendProactive - backthink/sinks.go: SetActiveSink/SetIMSink 晚注入(New后重建pusher,currentPusher 并发安全) - wire.go: 在 gw/bridge 建好后 bt.SetActiveSink(gw)/SetIMSink(bridge) - 投递链: think→parseProactive→ShouldPush→currentPusher.Push→gate→active(active_client)/IM(im_bridge) →record(route+送达数) - 测试: sinks/gateway proactive/channelbridge proactive; 后端 build/vet/test 全绿 - 注: -race 本机 TSan 不可用(环境); 多平台IM按msg.Platform匹配 owner 账号(单sink诚实); weixin 24h窗口按 ErrProactiveWindow 记录为 im_bridge 错误不静默