feat: add jetstream consumer api lifecycle

tests/NATS.Server.Tests/JetStreamConsumerApiTests.cs

@@ -0,0 +1,16 @@
+namespace NATS.Server.Tests;
+
+public class JetStreamConsumerApiTests
+{
+    [Fact]
+    public async Task Create_consumer_and_fetch_info_roundtrip()
+    {
+        await using var fixture = await JetStreamApiFixture.StartWithStreamAsync("ORDERS", "orders.*");
+
+        var create = await fixture.CreateConsumerAsync("ORDERS", "DUR", "orders.created");
+        create.Error.ShouldBeNull();
+
+        var info = await fixture.GetConsumerInfoAsync("ORDERS", "DUR");
+        info.Config.DurableName.ShouldBe("DUR");
+    }
+}