Eliminate PortTracker stub backlog by implementing Raft/file-store/stream/server/client/OCSP stubs and adding coverage. This makes all tracked stub features/tests executable and verified in the current porting phase.

dotnet/tests/ZB.MOM.NatsNet.Server.Tests/JetStream/CompressionInfoTests.cs

@@ -0,0 +1,39 @@
+// Copyright 2012-2026 The NATS Authors
+// Licensed under the Apache License, Version 2.0
+
+using Shouldly;
+using ZB.MOM.NatsNet.Server;
+
+namespace ZB.MOM.NatsNet.Server.Tests.JetStream;
+
+public sealed class CompressionInfoTests
+{
+    [Fact]
+    public void MarshalMetadata_UnmarshalMetadata_ShouldRoundTrip()
+    {
+        var ci = new CompressionInfo
+        {
+            Type = StoreCompression.S2Compression,
+            Original = 12345,
+            Compressed = 6789,
+        };
+
+        var payload = ci.MarshalMetadata();
+        payload.Length.ShouldBeGreaterThan(4);
+
+        var copy = new CompressionInfo();
+        var consumed = copy.UnmarshalMetadata(payload);
+
+        consumed.ShouldBe(payload.Length);
+        copy.Type.ShouldBe(StoreCompression.S2Compression);
+        copy.Original.ShouldBe(12345UL);
+        copy.Compressed.ShouldBe(6789UL);
+    }
+
+    [Fact]
+    public void UnmarshalMetadata_InvalidPrefix_ShouldReturnZero()
+    {
+        var ci = new CompressionInfo();
+        ci.UnmarshalMetadata([1, 2, 3, 4]).ShouldBe(0);
+    }
+}