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

session_owner_state_test.go

@@ -1,6 +1,39 @@
 package notify
 
-import "testing"
+import (
+	"sync"
+	"sync/atomic"
+	"testing"
+)
+
+func TestClaimOwnerSessionStopHasSingleCleanupWinner(t *testing.T) {
+	var state atomic.Int32
+	state.Store(ownerSessionStateRunning)
+
+	const contenders = 32
+	start := make(chan struct{})
+	var wg sync.WaitGroup
+	var winners atomic.Int32
+	wg.Add(contenders)
+	for range contenders {
+		go func() {
+			defer wg.Done()
+			<-start
+			if claimOwnerSessionStop(&state) {
+				winners.Add(1)
+			}
+		}()
+	}
+	close(start)
+	wg.Wait()
+
+	if got := winners.Load(); got != 1 {
+		t.Fatalf("session cleanup winners = %d, want 1", got)
+	}
+	if got := ownerSessionStateName(state.Load()); got != "stopping" {
+		t.Fatalf("claimed session state = %q, want stopping", got)
+	}
+}
 
 func TestClientOwnerSessionStateStartRollback(t *testing.T) {
 	client := NewClient().(*ClientCommon)