fix(host): dev site seed no longer targets the metrics port; validator rejects seed-vs-MetricsPort

src/ZB.MOM.WW.ScadaBridge.Host/StartupValidator.cs

@@ -124,6 +124,14 @@ public static class StartupValidator
                         _ => SeedNodePort(seed) != grpcPort,
                         $"entry '{seed}' must not target the gRPC port " +
                         $"({grpcPort}); seed nodes must reference Akka remoting ports");
+
+                    // Same failure mode as the gRPC guard: the Kestrel HTTP/1.1
+                    // metrics listener is not an Akka.Remote endpoint, so a seed on
+                    // it dials a doomed association forever.
+                    p.Require("ScadaBridge:Cluster:SeedNodes",
+                        _ => SeedNodePort(seed) != metricsPort,
+                        $"entry '{seed}' must not target the metrics port " +
+                        $"({metricsPort}); seed nodes must reference Akka remoting ports");
                 }
             })
             .ThrowIfInvalid();

src/ZB.MOM.WW.ScadaBridge.Host/appsettings.Site.json

@@ -11,9 +11,10 @@
       "NodeName": "node-a"
     },
     "Cluster": {
+      "_seedNodes": "Host-0xx: second entry is the FUTURE node-b remoting port (8085) for a two-node localhost site. It must be an Akka remoting endpoint — never this node's GrpcPort (8083) or MetricsPort (8084); StartupValidator rejects both.",
       "SeedNodes": [
         "akka.tcp://scadabridge@localhost:8082",
-        "akka.tcp://scadabridge@localhost:8084"
+        "akka.tcp://scadabridge@localhost:8085"
       ],
       "SplitBrainResolverStrategy": "keep-oldest",
       "StableAfter": "00:00:15",