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

client_connect_source.go

@@ -0,0 +1,121 @@
+package notify
+
+import (
+	"b612.me/notify/internal/transport"
+	"context"
+	"errors"
+	"net"
+	"time"
+)
+
+const (
+	clientConnectSourceConn    = "conn"
+	clientConnectSourceNetwork = "network"
+	clientConnectSourceTimeout = "timeout"
+	clientConnectSourceFactory = "factory"
+)
+
+var errClientReconnectSourceUnavailable = errors.New("client reconnect source is unavailable")
+
+type clientConnectSource struct {
+	kind    string
+	network string
+	addr    string
+	dialFn  func(context.Context) (net.Conn, error)
+}
+
+func newClientConnConnectSource(conn net.Conn) *clientConnectSource {
+	source := &clientConnectSource{kind: clientConnectSourceConn}
+	if conn == nil {
+		return source
+	}
+	if remoteAddr := conn.RemoteAddr(); remoteAddr != nil {
+		source.network = remoteAddr.Network()
+		source.addr = remoteAddr.String()
+	}
+	if source.network == "" {
+		if localAddr := conn.LocalAddr(); localAddr != nil {
+			source.network = localAddr.Network()
+		}
+	}
+	return source
+}
+
+func newClientNetworkConnectSource(network string, addr string) *clientConnectSource {
+	return &clientConnectSource{
+		kind:    clientConnectSourceNetwork,
+		network: network,
+		addr:    addr,
+		dialFn: func(context.Context) (net.Conn, error) {
+			return transport.Dial(network, addr)
+		},
+	}
+}
+
+func newClientTimeoutConnectSource(network string, addr string, timeout time.Duration) *clientConnectSource {
+	return &clientConnectSource{
+		kind:    clientConnectSourceTimeout,
+		network: network,
+		addr:    addr,
+		dialFn: func(context.Context) (net.Conn, error) {
+			return transport.DialTimeout(network, addr, timeout)
+		},
+	}
+}
+
+func newClientFactoryConnectSource(dialFn func(context.Context) (net.Conn, error)) *clientConnectSource {
+	return &clientConnectSource{
+		kind:   clientConnectSourceFactory,
+		dialFn: dialFn,
+	}
+}
+
+func (s *clientConnectSource) clone() *clientConnectSource {
+	if s == nil {
+		return nil
+	}
+	out := *s
+	return &out
+}
+
+func (s *clientConnectSource) canReconnect() bool {
+	return s != nil && s.dialFn != nil
+}
+
+func (s *clientConnectSource) isUDP() bool {
+	if s == nil {
+		return false
+	}
+	return transport.IsUDPNetwork(s.network)
+}
+
+func (s *clientConnectSource) dial(ctx context.Context) (net.Conn, error) {
+	if s == nil || s.dialFn == nil {
+		return nil, errClientReconnectSourceUnavailable
+	}
+	if ctx == nil {
+		ctx = context.Background()
+	}
+	return s.dialFn(ctx)
+}
+
+func (c *ClientCommon) setClientConnectSource(source *clientConnectSource) {
+	if c == nil {
+		return
+	}
+	if source == nil {
+		c.connectSource.Store(nil)
+		return
+	}
+	c.connectSource.Store(source.clone())
+}
+
+func (c *ClientCommon) clientConnectSourceSnapshot() *clientConnectSource {
+	if c == nil {
+		return nil
+	}
+	if source := c.connectSource.Load(); source != nil {
+		return source.clone()
+	}
+	return nil
+}