Fix OPC UA adapter: pass connection details, certificate stores, endpoint discovery

- DataConnectionActor now stores and passes connection details to adapter ConnectAsync
- DataConnectionManagerActor passes connection details when creating actor
- RealOpcUaClient uses DiscoveryClient for endpoint selection with no-security preference
- Added certificate trust store paths to prevent TrustedIssuerCertificates error
- Sanitize connection names for Akka actor paths (replace spaces)

src/ScadaLink.DataConnectionLayer/Actors/DataConnectionActor.cs

@@ -58,14 +58,18 @@ public class DataConnectionActor : UntypedActor, IWithStash, IWithTimers
     private int _totalSubscribed;
     private int _resolvedTags;
 
+    private readonly IDictionary<string, string> _connectionDetails;
+
     public DataConnectionActor(
         string connectionName,
         IDataConnection adapter,
-        DataConnectionOptions options)
+        DataConnectionOptions options,
+        IDictionary<string, string>? connectionDetails = null)
     {
         _connectionName = connectionName;
         _adapter = adapter;
         _options = options;
+        _connectionDetails = connectionDetails ?? new Dictionary<string, string>();
     }
 
     protected override void PreStart()
@@ -204,7 +208,7 @@ public class DataConnectionActor : UntypedActor, IWithStash, IWithTimers
     {
         _log.Debug("[{0}] Attempting connection...", _connectionName);
         var self = Self;
-        _adapter.ConnectAsync(new Dictionary<string, string>()).ContinueWith(t =>
+        _adapter.ConnectAsync(_connectionDetails).ContinueWith(t =>
         {
             if (t.IsCompletedSuccessfully)
                 return new ConnectResult(true, null);

src/ScadaLink.DataConnectionLayer/Actors/DataConnectionManagerActor.cs

@@ -44,9 +44,13 @@ public class DataConnectionManagerActor : ReceiveActor
         var adapter = _factory.Create(command.ProtocolType, command.ConnectionDetails);
 
         var props = Props.Create(() => new DataConnectionActor(
-            command.ConnectionName, adapter, _options));
+            command.ConnectionName, adapter, _options, command.ConnectionDetails));
 
-        var actorRef = Context.ActorOf(props, command.ConnectionName);
+        // Sanitize name for Akka actor path (replace spaces and invalid chars)
+        var actorName = new string(command.ConnectionName
+            .Select(c => char.IsLetterOrDigit(c) || "-_.*$+:@&=,!~';()".Contains(c) ? c : '-')
+            .ToArray());
+        var actorRef = Context.ActorOf(props, actorName);
         _connectionActors[command.ConnectionName] = actorRef;
 
         _log.Info("Created DataConnectionActor for {0} (protocol={1})",

src/ScadaLink.DataConnectionLayer/Adapters/RealOpcUaClient.cs

@@ -26,7 +26,10 @@ public class RealOpcUaClient : IOpcUaClient
             SecurityConfiguration = new SecurityConfiguration
             {
                 AutoAcceptUntrustedCertificates = true,
-                ApplicationCertificate = new CertificateIdentifier()
+                ApplicationCertificate = new CertificateIdentifier(),
+                TrustedIssuerCertificates = new CertificateTrustList { StorePath = Path.Combine(Path.GetTempPath(), "ScadaLink", "pki", "issuers") },
+                TrustedPeerCertificates = new CertificateTrustList { StorePath = Path.Combine(Path.GetTempPath(), "ScadaLink", "pki", "trusted") },
+                RejectedCertificateStore = new CertificateTrustList { StorePath = Path.Combine(Path.GetTempPath(), "ScadaLink", "pki", "rejected") }
             },
             ClientConfiguration = new ClientConfiguration { DefaultSessionTimeout = 60000 },
             TransportQuotas = new TransportQuotas { OperationTimeout = 15000 }
@@ -35,11 +38,26 @@ public class RealOpcUaClient : IOpcUaClient
         await appConfig.ValidateAsync(ApplicationType.Client);
         appConfig.CertificateValidator.CertificateValidation += (_, e) => e.Accept = true;
 
-        var endpoint = new EndpointDescription(endpointUrl)
+        // Discover endpoints from the server, pick the no-security one
+        EndpointDescription? endpoint;
+        try
         {
-            SecurityMode = MessageSecurityMode.None,
+#pragma warning disable CS0618
-            SecurityPolicyUri = SecurityPolicies.None
+            using var discoveryClient = DiscoveryClient.Create(new Uri(endpointUrl));
-        };
+#pragma warning restore CS0618
+#pragma warning disable CS0618
+            var endpoints = discoveryClient.GetEndpoints(null);
+#pragma warning restore CS0618
+            endpoint = endpoints
+                .Where(e => e.SecurityMode == MessageSecurityMode.None)
+                .FirstOrDefault() ?? endpoints.FirstOrDefault();
+        }
+        catch
+        {
+            // Fallback: construct endpoint description manually
+            endpoint = new EndpointDescription(endpointUrl);
+        }
+
         var endpointConfig = EndpointConfiguration.Create(appConfig);
         var configuredEndpoint = new ConfiguredEndpoint(null, endpoint, endpointConfig);