fix(notify): 根治低带宽控制面阻塞与传输写入卡死

- 为控制消息增加优先级、公平调度、队列字节预算和自适应批处理
- 支持可取消的写门等待，收紧 shared/dedicated bulk、stream 和 Reply 写入边界
- 修复 bulk reset/close、连接 handoff 和安全 profile 切换时序
- 保留旧取消与超时错误契约，新增阶段化 TransportSendError
- 增加 ReplyCtx、ReplyObjCtx、写超时配置及黑洞连接和竞态回归测试

server_config.go

@@ -1,6 +1,9 @@
 package notify
 
-import "context"
+import (
+	"context"
+	"time"
+)
 
 func (s *ServerCommon) DebugMode(dmg bool) {
 	s.mu.Lock()
@@ -14,6 +17,20 @@ func (s *ServerCommon) IsDebugMode() bool {
 	return s.debugMode
 }
 
+func (s *ServerCommon) SetReplyWriteTimeout(timeout time.Duration) {
+	if s == nil {
+		return
+	}
+	s.replyWriteTimeout.Store(int64(maxDuration(0, timeout)))
+}
+
+func (s *ServerCommon) ReplyWriteTimeout() time.Duration {
+	if s == nil {
+		return 0
+	}
+	return time.Duration(s.replyWriteTimeout.Load())
+}
+
 func (s *ServerCommon) ShowError(std bool) {
 	s.mu.Lock()
 	s.showError = std
@@ -57,12 +74,14 @@ func (s *ServerCommon) SetDefaultCommDecode(fn func([]byte, []byte) []byte) {
 }
 
 func (s *ServerCommon) SetDefaultLink(fn func(message *Message)) {
+	s.linkMu.Lock()
+	defer s.linkMu.Unlock()
 	s.defaultFns = fn
 }
 
 func (s *ServerCommon) SetLink(key string, fn func(*Message)) {
-	s.mu.Lock()
-	defer s.mu.Unlock()
+	s.linkMu.Lock()
+	defer s.linkMu.Unlock()
 	s.linkFns[key] = fn
 }