Wire DCL to Instance Actors for OPC UA tag value flow

- Add TagValueUpdate/ConnectionQualityChanged handlers to InstanceActor
- InstanceActor subscribes to DCL on PreStart based on DataSourceReference
- DeploymentManagerActor creates DCL connections on deploy and passes DCL ref
- AkkaHostedService creates DCL Manager Actor for tag subscriptions
- Move CreateConnectionCommand to Commons for cross-project access
- Add ConnectionConfig to FlattenedConfiguration for deployment packaging

src/ScadaLink.SiteRuntime/Actors/DeploymentManagerActor.cs

@@ -29,6 +29,7 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
     private readonly SiteStreamManager? _streamManager;
     private readonly SiteRuntimeOptions _options;
     private readonly ILogger<DeploymentManagerActor> _logger;
+    private readonly IActorRef? _dclManager;
     private readonly Dictionary<string, IActorRef> _instanceActors = new();
 
     public ITimerScheduler Timers { get; set; } = null!;
@@ -39,13 +40,15 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
         SharedScriptLibrary sharedScriptLibrary,
         SiteStreamManager? streamManager,
         SiteRuntimeOptions options,
-        ILogger<DeploymentManagerActor> logger)
+        ILogger<DeploymentManagerActor> logger,
+        IActorRef? dclManager = null)
     {
         _storage = storage;
         _compilationService = compilationService;
         _sharedScriptLibrary = sharedScriptLibrary;
         _streamManager = streamManager;
         _options = options;
+        _dclManager = dclManager;
         _logger = logger;
 
         // Lifecycle commands
@@ -192,6 +195,9 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
             return;
         }
 
+        // Ensure DCL connections exist for any data-sourced attributes
+        EnsureDclConnections(command.FlattenedConfigurationJson);
+
         // Create the Instance Actor immediately (no existing actor to replace)
         CreateInstanceActor(instanceName, command.FlattenedConfigurationJson);
 
@@ -342,6 +348,54 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
         _logger.LogInformation("Instance {Instance} deleted", instanceName);
     }
 
+    // ── DCL connection management ──
+
+    private readonly HashSet<string> _createdConnections = new();
+
+    /// <summary>
+    /// Parses the flattened config to find bound data connections and ensures
+    /// the DCL Manager has corresponding connection actors created.
+    /// </summary>
+    private void EnsureDclConnections(string configJson)
+    {
+        if (_dclManager == null) return;
+
+        try
+        {
+            var config = System.Text.Json.JsonSerializer.Deserialize<Commons.Types.Flattening.FlattenedConfiguration>(configJson);
+            if (config?.Connections == null) return;
+
+            foreach (var (name, connConfig) in config.Connections)
+            {
+                if (_createdConnections.Contains(name))
+                    continue;
+
+                var connectionDetails = new Dictionary<string, string>();
+                if (!string.IsNullOrEmpty(connConfig.ConfigurationJson))
+                {
+                    try
+                    {
+                        var parsed = System.Text.Json.JsonSerializer.Deserialize<Dictionary<string, string>>(connConfig.ConfigurationJson);
+                        if (parsed != null) connectionDetails = parsed;
+                    }
+                    catch { /* Ignore parse errors */ }
+                }
+
+                _dclManager.Tell(new Commons.Messages.DataConnection.CreateConnectionCommand(
+                    name, connConfig.Protocol, connectionDetails));
+
+                _createdConnections.Add(name);
+                _logger.LogInformation(
+                    "Created DCL connection {Connection} (protocol={Protocol})",
+                    name, connConfig.Protocol);
+            }
+        }
+        catch (Exception ex)
+        {
+            _logger.LogWarning(ex, "Failed to parse flattened config for DCL connections");
+        }
+    }
+
     // ── Debug View routing ──
 
     private void RouteDebugViewSubscribe(SubscribeDebugViewRequest request)
@@ -456,7 +510,8 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
             _sharedScriptLibrary,
             _streamManager,
             _options,
-            loggerFactory.CreateLogger<InstanceActor>()));
+            loggerFactory.CreateLogger<InstanceActor>(),
+            _dclManager));
 
         var actorRef = Context.ActorOf(props, instanceName);
         _instanceActors[instanceName] = actorRef;