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

file_transfer_adapter_test.go

@@ -0,0 +1,131 @@
+package notify
+
+import (
+	"bytes"
+	"context"
+	"os"
+	"path/filepath"
+	"sync"
+	"testing"
+	"time"
+)
+
+func TestSendFileUsesTransferKernelAndBuiltinFileReceiver(t *testing.T) {
+	server := NewServer().(*ServerCommon)
+	if err := UseModernPSKServer(server, integrationSharedSecret, integrationModernPSKOptions()); err != nil {
+		t.Fatalf("UseModernPSKServer failed: %v", err)
+	}
+	receiveDir := t.TempDir()
+	if err := server.SetFileReceiveDir(receiveDir); err != nil {
+		t.Fatalf("SetFileReceiveDir failed: %v", err)
+	}
+	var serverMu sync.Mutex
+	var serverEvents []FileEvent
+	server.SetFileHandler(func(event FileEvent) {
+		serverMu.Lock()
+		serverEvents = append(serverEvents, event)
+		serverMu.Unlock()
+	})
+	if err := server.Listen("tcp", "127.0.0.1:0"); err != nil {
+		t.Fatalf("server Listen failed: %v", err)
+	}
+	defer func() { _ = server.Stop() }()
+
+	client := NewClient().(*ClientCommon)
+	if err := UseModernPSKClient(client, integrationSharedSecret, integrationModernPSKOptions()); err != nil {
+		t.Fatalf("UseModernPSKClient failed: %v", err)
+	}
+	var clientMu sync.Mutex
+	var clientEvents []FileEvent
+	client.setFileEventObserver(func(event FileEvent) {
+		clientMu.Lock()
+		clientEvents = append(clientEvents, event)
+		clientMu.Unlock()
+	})
+	if err := client.Connect("tcp", server.listener.Addr().String()); err != nil {
+		t.Fatalf("client Connect failed: %v", err)
+	}
+	defer func() { _ = client.Stop() }()
+
+	payload := bytes.Repeat([]byte("send-file-transfer-kernel-"), 1024)
+	sendPath := filepath.Join(t.TempDir(), "payload.bin")
+	if err := os.WriteFile(sendPath, payload, 0o600); err != nil {
+		t.Fatalf("WriteFile failed: %v", err)
+	}
+
+	if err := client.SendFile(context.Background(), sendPath); err != nil {
+		t.Fatalf("SendFile failed: %v", err)
+	}
+
+	receivedPath := waitForSingleFileInDir(t, receiveDir, 2*time.Second)
+	received, err := os.ReadFile(receivedPath)
+	if err != nil {
+		t.Fatalf("ReadFile failed: %v", err)
+	}
+	if !bytes.Equal(received, payload) {
+		t.Fatalf("received payload mismatch: got %d want %d", len(received), len(payload))
+	}
+
+	clientSnapshots, err := GetClientTransferSnapshots(client)
+	if err != nil {
+		t.Fatalf("GetClientTransferSnapshots failed: %v", err)
+	}
+	serverSnapshots, err := GetServerTransferSnapshots(server)
+	if err != nil {
+		t.Fatalf("GetServerTransferSnapshots failed: %v", err)
+	}
+	if !containsFileTransferSnapshot(clientSnapshots) {
+		t.Fatalf("client snapshots do not contain file transfer metadata: %+v", clientSnapshots)
+	}
+	if !containsFileTransferSnapshot(serverSnapshots) {
+		t.Fatalf("server snapshots do not contain file transfer metadata: %+v", serverSnapshots)
+	}
+
+	clientMu.Lock()
+	serverMu.Lock()
+	defer clientMu.Unlock()
+	defer serverMu.Unlock()
+	if !containsFileEventKind(clientEvents, EnvelopeFileMeta) || !containsFileEventKind(clientEvents, EnvelopeFileEnd) {
+		t.Fatalf("client file events missing meta/end: %+v", clientEvents)
+	}
+	if !containsFileEventKind(serverEvents, EnvelopeFileMeta) || !containsFileEventKind(serverEvents, EnvelopeFileEnd) {
+		t.Fatalf("server file events missing meta/end: %+v", serverEvents)
+	}
+}
+
+func waitForSingleFileInDir(t *testing.T, dir string, timeout time.Duration) string {
+	t.Helper()
+	deadline := time.Now().Add(timeout)
+	for time.Now().Before(deadline) {
+		entries, err := os.ReadDir(dir)
+		if err == nil {
+			for _, entry := range entries {
+				if entry.IsDir() {
+					continue
+				}
+				return filepath.Join(dir, entry.Name())
+			}
+		}
+		time.Sleep(20 * time.Millisecond)
+	}
+	t.Fatalf("timed out waiting for received file in %s", dir)
+	return ""
+}
+
+func containsFileTransferSnapshot(list []TransferSnapshot) bool {
+	for _, snapshot := range list {
+		if snapshot.Metadata[fileTransferMetadataKindKey] == fileTransferMetadataKindValue && snapshot.State == TransferStateDone {
+			return true
+		}
+	}
+	return false
+}
+
+func containsFileEventKind(list []FileEvent, kind EnvelopeKind) bool {
+	for _, event := range list {
+		if event.Kind == kind {
+			return true
+		}
+	}
+	return false
+}