docs(code): correct comments stale after the perf remainder

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

@@ -101,10 +101,10 @@ public sealed class DriverInstanceActor : ReceiveActor, IWithTimers
     ///     state — a no-op when already Reconnecting or Connecting.
     /// </summary>
     public sealed record ForceReconnect;
-    /// <summary>One driver-published value. NOT sent to the parent by the subscription path any more — the
-    /// actor batches every data change into an <see cref="AttributeValueBatchPublished"/>. Still live as the
-    /// per-value message the parent fans onward (the dependency mux consumes it, and
-    /// <c>DriverHostActor.FanCommsLossToDependencyMux</c> fabricates it).
+    /// <summary>One driver-published value. <b>No production sender remains</b> — the subscription path
+    /// batches every data change into an <see cref="AttributeValueBatchPublished"/>, and the comms-loss fan
+    /// (<c>DriverHostActor.FanCommsLossToDependencyMux</c>), which was the last sender to fabricate this
+    /// message, now fabricates a batch too. The dependency mux still accepts it for tests and direct senders.
     /// <para><paramref name="StatusCode"/> is the driver's full OPC UA status code including its sub-code
     /// (#519) — not a severity bucket. Classify it with <see cref="OpcUaStatus.IsGood"/> and friends rather
     /// than comparing it to <see cref="OpcUaStatus.Good"/>.</para></summary>

src/Server/ZB.MOM.WW.OtOpcUa.Runtime/ServiceCollectionExtensions.cs

@@ -402,7 +402,7 @@ public static class ServiceCollectionExtensions
             }
 
             // Dependency mux must be spawned before DriverHostActor so the host can forward
-            // AttributeValuePublished into it from the very first driver spawn.
+            // AttributeValueBatchPublished into it from the very first driver spawn.
             var mux = system.ActorOf(DependencyMuxActor.Props(), DependencyMuxActorName);
             registry.Register<DependencyMuxActorKey>(mux);
 

src/Server/ZB.MOM.WW.OtOpcUa.Runtime/VirtualTags/DependencyMuxActor.cs

@@ -5,7 +5,7 @@ using ZB.MOM.WW.OtOpcUa.Runtime.Drivers;
 namespace ZB.MOM.WW.OtOpcUa.Runtime.VirtualTags;
 
 /// <summary>
-///     Per-node fan-out router from <see cref="DriverInstanceActor.AttributeValuePublished"/>
+///     Per-node fan-out router from <see cref="DriverInstanceActor.AttributeValueBatchPublished"/>
 ///     to interested <see cref="VirtualTagActor"/> instances. VirtualTagActor sends
 ///     <see cref="RegisterInterest"/> on start-up listing the tag refs it depends on; the mux
 ///     keeps a map of <c>tagRef → Set&lt;IActorRef&gt;</c> and on every ingress forwards each
@@ -16,11 +16,12 @@ namespace ZB.MOM.WW.OtOpcUa.Runtime.VirtualTags;
 ///     node). The ONLY driver ingress is the batched
 ///     <see cref="DriverInstanceActor.AttributeValueBatchPublished"/> — one envelope per driver
 ///     production burst, which the mux filters per item. The per-value
-///     <see cref="DriverInstanceActor.AttributeValuePublished"/> receive stays for the comms-loss fan
-///     ALONE: <c>DriverHostActor.FanCommsLossToDependencyMux</c> fabricates that message and Tells this
-///     mux directly, never through the host's own receive.
+///     <see cref="DriverInstanceActor.AttributeValuePublished"/> receive has <b>no production sender left
+///     at all</b>: the comms-loss fan (<c>DriverHostActor.FanCommsLossToDependencyMux</c>) was its last
+///     one and now fabricates an <c>AttributeValueBatchPublished</c> instead. The receive is kept for
+///     tests and direct senders — treat it as dead in production.
 ///
-///     <b>The mux emits ONLY batches</b> (the comms-loss fan as a single-item one), so a subscriber's
+///     <b>The mux emits ONLY batches</b>, so a subscriber's
 ///     batch receive is its complete hot path. Every subscriber keeps a per-value
 ///     <see cref="VirtualTagActor.DependencyValueChanged"/> receive as well, for direct senders and tests.
 ///     The mux is deliberately not a DPS subscriber — virtual-tag evaluation is local to each node and
@@ -115,8 +116,8 @@ public sealed class DependencyMuxActor : ReceiveActor
         {
             // A single-item batch, so the mux emits exactly ONE message shape and every subscriber needs
             // only the batch receive on its hot path. One list per subscriber: batch ownership transfers
-            // to the receiver, so a shared list must never cross mailboxes. This is the comms-loss fan
-            // (one ref, on a driver disconnect), not the steady value path — the extra allocation is noise.
+            // to the receiver, so a shared list must never cross mailboxes. Nothing in production reaches
+            // this path (see the class doc) — the extra allocation is noise on a test-only seam.
             sub.Tell(new VirtualTagActor.DependencyValueBatch(new[] { dep }));
         }
     }