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

transport_conn.go

@@ -9,9 +9,14 @@ import (
 )
 
 type TransportConn struct {
-	logical        *LogicalConn
-	generation     uint64
-	remoteAddr     net.Addr
+	logical    *LogicalConn
+	generation uint64
+	remoteAddr net.Addr
+	// binding pins this view to the physical connection that produced it. A
+	// logical session may replace its transport while an operation is in
+	// flight; using the logical's current binding at that point would cross the
+	// reconnect boundary.
+	binding        *transportBinding
 	attached       bool
 	hasRuntimeConn bool
 }
@@ -19,6 +24,7 @@ type TransportConn struct {
 const (
 	transportStreamReadBufferSize = 1024 * 1024
 	transportPacketReadBufferSize = 64 * 1024
+	transportFrameMaxPayloadBytes = 64 * 1024 * 1024
 )
 
 func streamReadBuffer() []byte {
@@ -120,6 +126,7 @@ func (c *LogicalConn) currentTransportConnSnapshot() *TransportConn {
 				logical:        logical,
 				generation:     c.transportGenerationSnapshot(),
 				remoteAddr:     remoteAddr,
+				binding:        c.transportBindingSnapshot(),
 				attached:       true,
 				hasRuntimeConn: hasRuntimeConn,
 			}
@@ -132,6 +139,7 @@ func (c *LogicalConn) currentTransportConnSnapshot() *TransportConn {
 		logical:        logical,
 		generation:     c.transportGenerationSnapshot(),
 		remoteAddr:     remoteAddr,
+		binding:        c.transportBindingSnapshot(),
 		attached:       true,
 		hasRuntimeConn: hasRuntimeConn,
 	}
@@ -197,13 +205,42 @@ func (t *TransportConn) IsCurrent() bool {
 	current := logical.CurrentTransportConn()
 	if current == nil {
 		return false
-	}
-	if current.generation != t.generation {
+	} else if current.generation != t.generation {
 		return false
+	} else if t.binding != nil {
+		return current.binding == t.binding
 	}
 	return transportConnAddrString(current.remoteAddr) == transportConnAddrString(t.remoteAddr)
 }
 
+// serverTransportBindingSnapshot returns the physical binding pinned by an
+// explicit transport. The logical fallback preserves compatibility for
+// package-local callers that construct TransportConn values directly.
+func serverTransportBindingSnapshot(logical *LogicalConn, transport *TransportConn) *transportBinding {
+	if transport != nil && transport.binding != nil {
+		return transport.binding
+	}
+	if logical == nil {
+		return nil
+	}
+	return logical.transportBindingSnapshot()
+}
+
+// serverTransportBindingSnapshotForConn preserves an inbound socket handoff:
+// peer attach can transfer the same physical conn from a temporary logical
+// peer to its stable logical peer. In that case the destination's binding owns
+// the exact inbound conn and must serialize the reply. A different replacement
+// conn can never satisfy this identity check, so explicit transport sends stay
+// pinned to their original binding.
+func serverTransportBindingSnapshotForConn(logical *LogicalConn, transport *TransportConn, conn net.Conn) *transportBinding {
+	if conn != nil && logical != nil {
+		if current := logical.transportBindingSnapshot(); current != nil && current.connSnapshot() == conn {
+			return current
+		}
+	}
+	return serverTransportBindingSnapshot(logical, transport)
+}
+
 func transportConnAddrString(addr net.Addr) string {
 	if addr == nil {
 		return ""