feat(go): generate unique load simulator frames

go/vehicle-gateway/internal/loadsim/runner_test.go

@@ -54,6 +54,48 @@ func TestRunnerDialsTargetConnectionsAndWritesFrames(t *testing.T) {
 	}
 }
 
+func TestRunnerWritesVariantFrames(t *testing.T) {
+	writes := make(chan []byte, 8)
+	runner := Runner{
+		Dial: func(ctx context.Context, network, addr string) (net.Conn, error) {
+			return &recordingConn{
+				write: func(p []byte) (int, error) {
+					cp := append([]byte(nil), p...)
+					select {
+					case writes <- cp:
+					default:
+					}
+					return len(p), nil
+				},
+				close: func() error { return nil },
+			}, nil
+		},
+	}
+
+	stats, err := runner.Run(context.Background(), Config{
+		Protocol:             ProtocolJT808,
+		Addr:                 "127.0.0.1:808",
+		Connections:          1,
+		ConnectRatePerSecond: 1000,
+		SendInterval:         time.Millisecond,
+		Duration:             6 * time.Millisecond,
+		Template:             "0200",
+		SendFrames:           true,
+	})
+	if err != nil {
+		t.Fatalf("Run() error = %v", err)
+	}
+	if stats.FramesWritten < 2 {
+		t.Fatalf("FramesWritten = %d, want at least 2", stats.FramesWritten)
+	}
+
+	first := <-writes
+	second := <-writes
+	if string(first) == string(second) {
+		t.Fatal("runner wrote byte-identical frames; want per-frame variants")
+	}
+}
+
 func TestRunnerCanHoldConnectionsWithoutWritingFrames(t *testing.T) {
 	var writes atomic.Int64
 	runner := Runner{