fix(notify): 修复传输生命周期竞态，完善背压与协议边界

- 完善 stream/bulk DataID 分配、预留和双向命名空间，修复并发打开及 dedicated/shared 回退时的 ID 冲突
- 将收发、回复、恢复任务和 sidecar 绑定原始会话与物理连接，防止重连后的旧消息误操作新连接
- 加强 close/reset 身份校验及实例移除检查，修复 dedicated attach 失败、通道引用和资源回收竞态
- 收紧批量发送器停止准入，确保在途入队完成后统一清理请求、缓冲区和等待者
- 修复 record 满队列死锁、取消时序号消耗及关闭竞态，确保关闭有界并返回真实错误
- 增加协商式 record 逻辑半关闭，保留反向 ACK；通过 reset 传递 RecordFailure，避免背压掩盖原始失败原因
- 补齐帧长度、批次数量、序号溢出和未确认窗口校验，提前拒绝超限数据并按字节预算拆批
- 为入站分发增加全局及单连接的条数、字节预算和阻塞背压，关闭时唤醒等待者，消除正常断连日志噪音
- 完善 bulk 窗口释放失败处理与传输诊断，补充并发、重连、背压、协议边界及真实 TCP 回归覆盖

record_negotiation.go

@@ -1,9 +1,11 @@
 package notify
 
 const (
-	recordStreamMetadataCapBatchAckKey = "_notify.record_cap_batch_ack"
-	recordStreamMetadataUseBatchAckKey = "_notify.record_use_batch_ack"
-	recordStreamMetadataEnabledValue   = "1"
+	recordStreamMetadataCapBatchAckKey  = "_notify.record_cap_batch_ack"
+	recordStreamMetadataUseBatchAckKey  = "_notify.record_use_batch_ack"
+	recordStreamMetadataCapHalfCloseKey = "_notify.record_cap_half_close"
+	recordStreamMetadataUseHalfCloseKey = "_notify.record_use_half_close"
+	recordStreamMetadataEnabledValue    = "1"
 )
 
 func advertiseRecordStreamOpenMetadata(metadata StreamMetadata) StreamMetadata {
@@ -11,7 +13,9 @@ func advertiseRecordStreamOpenMetadata(metadata StreamMetadata) StreamMetadata {
 	if metadata == nil {
 		metadata = make(StreamMetadata, 1)
 	}
+	delete(metadata, recordStreamMetadataUseHalfCloseKey)
 	metadata[recordStreamMetadataCapBatchAckKey] = recordStreamMetadataEnabledValue
+	metadata[recordStreamMetadataCapHalfCloseKey] = recordStreamMetadataEnabledValue
 	return metadata
 }
 
@@ -20,13 +24,17 @@ func negotiateRecordStreamOpenMetadata(channel StreamChannel, metadata StreamMet
 	if normalizeStreamChannel(channel) != StreamRecordChannel {
 		return metadata, nil
 	}
-	if metadata[recordStreamMetadataCapBatchAckKey] != recordStreamMetadataEnabledValue {
-		return metadata, nil
+	response := make(StreamMetadata)
+	if metadata[recordStreamMetadataCapBatchAckKey] == recordStreamMetadataEnabledValue {
+		metadata[recordStreamMetadataUseBatchAckKey] = recordStreamMetadataEnabledValue
+		response[recordStreamMetadataUseBatchAckKey] = recordStreamMetadataEnabledValue
 	}
-	metadata[recordStreamMetadataUseBatchAckKey] = recordStreamMetadataEnabledValue
-	return metadata, StreamMetadata{
-		recordStreamMetadataUseBatchAckKey: recordStreamMetadataEnabledValue,
+	delete(metadata, recordStreamMetadataUseHalfCloseKey)
+	if metadata[recordStreamMetadataCapHalfCloseKey] == recordStreamMetadataEnabledValue {
+		metadata[recordStreamMetadataUseHalfCloseKey] = recordStreamMetadataEnabledValue
+		response[recordStreamMetadataUseHalfCloseKey] = recordStreamMetadataEnabledValue
 	}
+	return metadata, response
 }
 
 func mergeStreamMetadata(base StreamMetadata, overlay StreamMetadata) StreamMetadata {
@@ -46,3 +54,7 @@ func mergeStreamMetadata(base StreamMetadata, overlay StreamMetadata) StreamMeta
 func recordStreamUseBatchAck(metadata StreamMetadata) bool {
 	return metadata[recordStreamMetadataUseBatchAckKey] == recordStreamMetadataEnabledValue
 }
+
+func recordStreamUseHalfClose(metadata StreamMetadata) bool {
+	return metadata[recordStreamMetadataUseHalfCloseKey] == recordStreamMetadataEnabledValue
+}