feat(siteeventlog): emit deployment + instance_lifecycle events (M1.6)

DeploymentManagerActor now fire-and-forgets a 'deployment' site operational
event on deploy/enable/disable/delete outcomes (Info on success, Error on
failure), source 'DeploymentManagerActor'. The disable/delete events are emitted
from the existing PipeTo continuations (safe: reads only the immutable
_serviceProvider and fire-and-forgets).

InstanceActor now emits an 'instance_lifecycle' Info event in PreStart (started)
and a new PostStop (stopped) — covering start/stop/enable/disable/redeploy/
failover transitions from the instance's own vantage point. Both actors already
hold _serviceProvider; no ctor change.

Resolution is optional and LogEventAsync is fire-and-forget so a logging failure
never affects the deployment pipeline or instance lifecycle.

src/ZB.MOM.WW.ScadaBridge.SiteRuntime/Actors/InstanceActor.cs

@@ -1,5 +1,6 @@
 using Akka.Actor;
 using Microsoft.CodeAnalysis.Scripting;
+using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 using ZB.MOM.WW.ScadaBridge.Commons.Messages.DataConnection;
 using ZB.MOM.WW.ScadaBridge.Commons.Messages.DebugView;
@@ -9,6 +10,7 @@ using ZB.MOM.WW.ScadaBridge.Commons.Messages.Streaming;
 using ZB.MOM.WW.ScadaBridge.Commons.Types.Enums;
 using ZB.MOM.WW.ScadaBridge.Commons.Types.Flattening;
 using ZB.MOM.WW.ScadaBridge.HealthMonitoring;
+using ZB.MOM.WW.ScadaBridge.SiteEventLogging;
 using ZB.MOM.WW.ScadaBridge.SiteRuntime.Persistence;
 using ZB.MOM.WW.ScadaBridge.SiteRuntime.Scripts;
 using ZB.MOM.WW.ScadaBridge.SiteRuntime.Streaming;
@@ -164,6 +166,11 @@ public class InstanceActor : ReceiveActor
         base.PreStart();
         _logger.LogInformation("InstanceActor started for {Instance}", _instanceUniqueName);
 
+        // M1.6: operational `instance_lifecycle` event — instance started.
+        // An instance starts on deploy, on enable (DeploymentManager re-creates
+        // the actor), and on failover/restart; this single point covers them all.
+        LogLifecycleEvent($"Instance {_instanceUniqueName} started");
+
         // Asynchronously load static overrides from SQLite and pipe to self
         var self = Self;
         _storage.GetStaticOverridesAsync(_instanceUniqueName).ContinueWith(t =>
@@ -180,6 +187,29 @@ public class InstanceActor : ReceiveActor
         SubscribeToDcl();
     }
 
+    /// <inheritdoc />
+    protected override void PostStop()
+    {
+        // M1.6: operational `instance_lifecycle` event — instance stopped. An
+        // instance stops on disable, delete, redeployment, and graceful shutdown;
+        // this single point covers them all.
+        LogLifecycleEvent($"Instance {_instanceUniqueName} stopped");
+        base.PostStop();
+    }
+
+    /// <summary>
+    /// M1.6: fire-and-forget an <c>instance_lifecycle</c> operational event to the
+    /// optional <see cref="ISiteEventLogger"/>. Resolved optionally and never
+    /// awaited so a logging failure cannot affect the instance lifecycle
+    /// (matching the established ScriptActor/ScriptExecutionActor pattern).
+    /// </summary>
+    private void LogLifecycleEvent(string message)
+    {
+        _ = _serviceProvider?.GetService<ISiteEventLogger>()?.LogEventAsync(
+            "instance_lifecycle", "Info", _instanceUniqueName,
+            $"InstanceActor:{_instanceUniqueName}", message);
+    }
+
     /// <inheritdoc />
     protected override SupervisorStrategy SupervisorStrategy()
     {