feat(notify): 重构通信内核并补齐 stream/bulk/record/transfer 能力

- 引入 LogicalConn/TransportConn 分层，ClientConn 保留兼容适配层
  - 新增 Stream、Bulk、RecordStream 三条数据面能力及对应控制路径
  - 完成 transfer/file 传输内核与状态快照、诊断能力
  - 补齐 reconnect、inbound dispatcher、modern psk 等基础模块
  - 增加大规模回归、并发与基准测试覆盖
  - 更新依赖库

server_outbound_route_test.go

@@ -0,0 +1,60 @@
+package notify
+
+import (
+	"net"
+	"testing"
+)
+
+func TestServerResolveOutboundTransportNilLogical(t *testing.T) {
+	server := NewServer().(*ServerCommon)
+
+	if route := server.resolveOutboundRoute(nil); route.logical != nil || route.transport != nil {
+		t.Fatalf("nil logical route mismatch: %+v", route)
+	}
+	if transport := server.resolveOutboundTransport(nil); transport != nil {
+		t.Fatalf("resolveOutboundTransport(nil) = %+v, want nil", transport)
+	}
+}
+
+func TestServerResolveOutboundTransportUsesCurrentGeneration(t *testing.T) {
+	server := NewServer().(*ServerCommon)
+
+	firstLeft, firstRight := net.Pipe()
+	defer firstRight.Close()
+	logical := server.bootstrapAcceptedLogical("outbound-route", nil, firstLeft)
+	if logical == nil {
+		t.Fatal("bootstrapAcceptedLogical should return logical")
+	}
+
+	first := server.resolveOutboundTransport(logical)
+	if first == nil {
+		t.Fatal("initial outbound transport should exist")
+	}
+	if !first.IsCurrent() {
+		t.Fatal("initial outbound transport should be current")
+	}
+
+	secondLeft, secondRight := net.Pipe()
+	defer secondLeft.Close()
+	defer secondRight.Close()
+	if err := server.attachAcceptedLogicalTransport(logical, secondLeft.RemoteAddr(), secondLeft); err != nil {
+		t.Fatalf("attachAcceptedLogicalTransport failed: %v", err)
+	}
+
+	second := server.resolveOutboundTransport(logical)
+	if second == nil {
+		t.Fatal("resolved outbound transport after reattach should exist")
+	}
+	if !second.IsCurrent() {
+		t.Fatal("resolved outbound transport after reattach should be current")
+	}
+	if got, want := second.TransportGeneration(), logical.clientConnTransportGenerationSnapshot(); got != want {
+		t.Fatalf("resolved outbound generation = %d, want %d", got, want)
+	}
+	if first.TransportGeneration() == second.TransportGeneration() {
+		t.Fatalf("outbound generation should change after reattach: first=%d second=%d", first.TransportGeneration(), second.TransportGeneration())
+	}
+	if first.IsCurrent() {
+		t.Fatal("first outbound transport should become stale after reattach")
+	}
+}