fix(runtime): re-provision a driver child after a supervision restart (archreview 03/S6, S16)

src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Drivers/DriverInstanceActor.cs

@@ -42,6 +42,25 @@ public sealed class DriverInstanceActor : ReceiveActor, IWithTimers
     /// restored → Good) — independently of alarm transitions, since a comms-lost driver emits no alarm
     /// events. Fire-and-forget, mirroring <see cref="DeltaApplied"/>.</summary>
     public sealed record ConnectivityChanged(string DriverInstanceId, bool Connected);
+
+    /// <summary>
+    ///     Sent to the parent from <see cref="PostRestart"/> so the host re-provisions THIS incarnation
+    ///     (archreview 03/S6, 03/S16).
+    /// </summary>
+    /// <remarks>
+    ///     A supervision restart recreates the actor object in place: the desired subscription sets are gone
+    ///     (they are instance fields), and <c>PreRestart</c> has already run <see cref="PostStop"/> — which
+    ///     called <see cref="IDriver.ShutdownAsync"/> on the driver object the Props closure re-uses. Nothing
+    ///     else re-sends <see cref="InitializeRequested"/>: its only sender is
+    ///     <c>DriverHostActor.SpawnChild</c>, and a restart does NOT respawn (the child's
+    ///     <see cref="IActorRef"/> is unchanged, so the host is not otherwise notified that a new incarnation
+    ///     exists at all). Without this the restarted child sits in <c>Connecting</c> forever around a
+    ///     shut-down driver, with nothing subscribed — silently, since Akka logs the fault but the recovery
+    ///     is invisible.
+    /// </remarks>
+    /// <param name="DriverInstanceId">The driver instance that was restarted.</param>
+    /// <param name="Reason">The type name of the exception that tripped supervision, for the host's log.</param>
+    public sealed record ReprovisionRequested(string DriverInstanceId, string Reason);
     public sealed record ApplyDelta(string DriverConfigJson, CorrelationId Correlation);
     public sealed record ApplyResult(bool Success, string? Reason, CorrelationId Correlation);
     /// <summary>
@@ -375,6 +394,20 @@ public sealed class DriverInstanceActor : ReceiveActor, IWithTimers
         Timers.StartPeriodicTimer("health-poll", HealthPollTick.Instance, _healthPollInterval);
     }
 
+    /// <inheritdoc />
+    /// <remarks>
+    ///     Ask the host to re-provision this incarnation — see <see cref="ReprovisionRequested"/> for why a
+    ///     supervision restart otherwise leaves a dead child. <c>base.PostRestart</c> runs first because it
+    ///     runs <see cref="PreStart"/>, which re-attaches the rediscovery / host-status sources and restarts
+    ///     the health timer; the reprovision is the part <see cref="PreStart"/> cannot do, since only the
+    ///     host knows this driver's config and desired set.
+    /// </remarks>
+    protected override void PostRestart(Exception reason)
+    {
+        base.PostRestart(reason);
+        Context.Parent.Tell(new ReprovisionRequested(_driverInstanceId, reason.GetType().Name));
+    }
+
     private void Stubbed()
     {
         // Stubbed drivers accept the standard message contracts but return deterministic