feat: add route propagation and bootstrap js gateway leaf services

tests/NATS.Server.Tests/JetStreamStartupTests.cs

@@ -0,0 +1,13 @@
+namespace NATS.Server.Tests;
+
+public class JetStreamStartupTests
+{
+    [Fact]
+    public async Task JetStream_enabled_server_starts_service()
+    {
+        await using var server = await TestServerFactory.CreateJetStreamEnabledAsync();
+        await server.WaitForReadyAsync();
+
+        server.Stats.JetStreamEnabled.ShouldBeTrue();
+    }
+}