fix: wire DCL tag value delivery, alarm evaluation, and snapshot timestamps

Three runtime bugs fixed:
- DataConnectionActor: TagValueReceived/TagResolutionSucceeded/Failed not
  handled in any Become state — OPC UA values went to dead letters. Added
  initial read after subscribe to seed current values immediately.
- AlarmActor: ParseEvalConfig expected "attributeName"/"matchValue"/"min"/
  "max" keys but seed data uses "attribute"/"value"/"high"/"low". Added
  support for both conventions and !=prefix for not-equal matching.
- InstanceActor: snapshots reported all alarms (including unevaluated) with
  correct priorities and source timestamps instead of current UTC. Removed
  bogus Vibration template attribute that shadowed Speed's tag mapping.

src/ScadaLink.SiteRuntime/Actors/InstanceActor.cs

@@ -42,7 +42,10 @@ public class InstanceActor : ReceiveActor
     private readonly IServiceProvider? _serviceProvider;
     private readonly Dictionary<string, object?> _attributes = new();
     private readonly Dictionary<string, string> _attributeQualities = new();
+    private readonly Dictionary<string, DateTimeOffset> _attributeTimestamps = new();
     private readonly Dictionary<string, AlarmState> _alarmStates = new();
+    private readonly Dictionary<string, DateTimeOffset> _alarmTimestamps = new();
+    private readonly Dictionary<string, int> _alarmPriorities = new();
     private readonly Dictionary<string, IActorRef> _scriptActors = new();
     private readonly Dictionary<string, IActorRef> _alarmActors = new();
     private FlattenedConfiguration? _configuration;
@@ -124,6 +127,7 @@ public class InstanceActor : ReceiveActor
 
         // Handle tag value updates from DCL — convert to AttributeValueChanged
         Receive<TagValueUpdate>(HandleTagValueUpdate);
+        Receive<SubscribeTagsResponse>(_ => { }); // Ack from DCL subscribe — no action needed
         Receive<ConnectionQualityChanged>(HandleConnectionQualityChanged);
 
         // WP-16: Handle alarm state changes from Alarm Actors (Tell pattern)
@@ -267,6 +271,7 @@ public class InstanceActor : ReceiveActor
         // WP-24: State mutation serialized through this actor
         _attributes[changed.AttributeName] = changed.Value;
         _attributeQualities[changed.AttributeName] = changed.Quality;
+        _attributeTimestamps[changed.AttributeName] = changed.Timestamp;
 
         PublishAndNotifyChildren(changed);
     }
@@ -338,6 +343,7 @@ public class InstanceActor : ReceiveActor
     private void HandleAlarmStateChanged(AlarmStateChanged changed)
     {
         _alarmStates[changed.AlarmName] = changed.State;
+        _alarmTimestamps[changed.AlarmName] = changed.Timestamp;
 
         // WP-23: Publish to site-wide stream
         _streamManager?.PublishAlarmStateChanged(changed);
@@ -358,20 +364,21 @@ public class InstanceActor : ReceiveActor
         _debugSubscribers[subscriptionId] = Sender;
 
         // Build snapshot from current state
+        var now = DateTimeOffset.UtcNow;
         var attributeValues = _attributes.Select(kvp => new AttributeValueChanged(
             _instanceUniqueName,
             kvp.Key,
             kvp.Key,
             kvp.Value,
             _attributeQualities.GetValueOrDefault(kvp.Key, "Good"),
-            DateTimeOffset.UtcNow)).ToList();
+            _attributeTimestamps.GetValueOrDefault(kvp.Key, now))).ToList();
 
-        var alarmStates = _alarmStates.Select(kvp => new AlarmStateChanged(
+        var alarmStates = _alarmActors.Keys.Select(name => new AlarmStateChanged(
             _instanceUniqueName,
-            kvp.Key,
-            kvp.Value,
-            0, // Priority not tracked in _alarmStates; would need separate tracking
-            DateTimeOffset.UtcNow)).ToList();
+            name,
+            _alarmStates.GetValueOrDefault(name, AlarmState.Normal),
+            _alarmPriorities.GetValueOrDefault(name, 0),
+            _alarmTimestamps[name])).ToList();
 
         var snapshot = new DebugViewSnapshot(
             _instanceUniqueName,
@@ -407,20 +414,21 @@ public class InstanceActor : ReceiveActor
     /// </summary>
     private void HandleDebugSnapshot(DebugSnapshotRequest request)
     {
+        var now = DateTimeOffset.UtcNow;
         var attributeValues = _attributes.Select(kvp => new AttributeValueChanged(
             _instanceUniqueName,
             kvp.Key,
             kvp.Key,
             kvp.Value,
             _attributeQualities.GetValueOrDefault(kvp.Key, "Good"),
-            DateTimeOffset.UtcNow)).ToList();
+            _attributeTimestamps.GetValueOrDefault(kvp.Key, now))).ToList();
 
-        var alarmStates = _alarmStates.Select(kvp => new AlarmStateChanged(
+        var alarmStates = _alarmActors.Keys.Select(name => new AlarmStateChanged(
             _instanceUniqueName,
-            kvp.Key,
-            kvp.Value,
-            0,
-            DateTimeOffset.UtcNow)).ToList();
+            name,
+            _alarmStates.GetValueOrDefault(name, AlarmState.Normal),
+            _alarmPriorities.GetValueOrDefault(name, 0),
+            _alarmTimestamps[name])).ToList();
 
         var snapshot = new DebugViewSnapshot(
             _instanceUniqueName,
@@ -562,6 +570,8 @@ public class InstanceActor : ReceiveActor
 
             var actorRef = Context.ActorOf(props, $"alarm-{alarm.CanonicalName}");
             _alarmActors[alarm.CanonicalName] = actorRef;
+            _alarmPriorities[alarm.CanonicalName] = alarm.PriorityLevel;
+            _alarmTimestamps[alarm.CanonicalName] = DateTimeOffset.UtcNow;
         }
 
         _logger.LogInformation(