batch35: add and verify test wave T1

dotnet/tests/ZB.MOM.NatsNet.Server.Tests/ImplBacklog/JetStreamBatchingTests.cs

@@ -6,6 +6,31 @@ namespace ZB.MOM.NatsNet.Server.Tests.ImplBacklog;
 
 public sealed class JetStreamBatchingTests
 {
+    [Fact] // T:730
+    public void JetStreamAtomicBatchPublishEncode_ShouldSucceed()
+    {
+        var encoded = JetStreamCluster.EncodeStreamMsgAllowCompressAndBatch(
+            "ORDERS.created",
+            "_R_",
+            [1, 2, 3],
+            [10, 11, 12, 13],
+            sequence: 42,
+            timestamp: 123_456,
+            sourced: true,
+            batchId: "b1",
+            batchSequence: 2,
+            batchCommit: false);
+
+        encoded.Length.ShouldBeGreaterThan(0);
+
+        var (batchId, batchSequence, op, payload, error) = JetStreamCluster.DecodeBatchMsg(encoded.AsSpan(1));
+        error.ShouldBeNull();
+        batchId.ShouldBe("b1");
+        batchSequence.ShouldBe(2UL);
+        op.ShouldBe(EntryOp.StreamMsgOp);
+        payload.ShouldNotBeNull();
+    }
+
     [Fact] // T:743
     public void JetStreamAtomicBatchPublishExpectedLastSubjectSequence_ShouldSucceed()
     {