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

stream_flow_test.go

@@ -0,0 +1,107 @@
+package notify
+
+import (
+	"context"
+	"sync"
+	"testing"
+	"time"
+)
+
+func TestStreamFlowControllerBlocksUntilWindowReleased(t *testing.T) {
+	controller := newStreamFlowController(streamConfig{
+		ChunkSize:                 4,
+		InboundQueueLimit:         1,
+		InboundBufferedBytesLimit: 4,
+		OutboundWindowBytes:       4,
+		OutboundMaxInFlightChunks: 1,
+	})
+
+	releaseFirst, err := controller.acquire(context.Background(), 4)
+	if err != nil {
+		t.Fatalf("first acquire failed: %v", err)
+	}
+	defer releaseFirst()
+
+	secondDone := make(chan error, 1)
+	go func() {
+		releaseSecond, err := controller.acquire(context.Background(), 4)
+		if err == nil && releaseSecond != nil {
+			releaseSecond()
+		}
+		secondDone <- err
+	}()
+
+	select {
+	case err := <-secondDone:
+		t.Fatalf("second acquire should block, got err = %v", err)
+	case <-time.After(80 * time.Millisecond):
+	}
+
+	releaseFirst()
+
+	select {
+	case err := <-secondDone:
+		if err != nil {
+			t.Fatalf("second acquire failed after release: %v", err)
+		}
+	case <-time.After(time.Second):
+		t.Fatal("timed out waiting for second acquire")
+	}
+}
+
+func TestStreamFlowControllerAdmitsRequestsFIFO(t *testing.T) {
+	controller := newStreamFlowController(streamConfig{
+		ChunkSize:                 4,
+		InboundQueueLimit:         1,
+		InboundBufferedBytesLimit: 4,
+		OutboundWindowBytes:       4,
+		OutboundMaxInFlightChunks: 1,
+	})
+
+	releaseFirst, err := controller.acquire(context.Background(), 4)
+	if err != nil {
+		t.Fatalf("first acquire failed: %v", err)
+	}
+
+	orderCh := make(chan int, 2)
+	releaseCh := make(chan struct{})
+	startAcquire := func(id int, start <-chan struct{}, wg *sync.WaitGroup) {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			<-start
+			release, err := controller.acquire(context.Background(), 4)
+			if err != nil {
+				t.Errorf("acquire %d failed: %v", id, err)
+				return
+			}
+			orderCh <- id
+			<-releaseCh
+			release()
+		}()
+	}
+
+	var wg sync.WaitGroup
+	startSecond := make(chan struct{})
+	startThird := make(chan struct{})
+	startAcquire(2, startSecond, &wg)
+	startAcquire(3, startThird, &wg)
+
+	close(startSecond)
+	time.Sleep(20 * time.Millisecond)
+	close(startThird)
+	time.Sleep(50 * time.Millisecond)
+	releaseFirst()
+
+	first := <-orderCh
+	if first != 2 {
+		t.Fatalf("first admitted request = %d, want 2", first)
+	}
+	close(releaseCh)
+	wg.Wait()
+
+	second := <-orderCh
+	if second != 3 {
+		t.Fatalf("second admitted request = %d, want 3", second)
+	}
+}