perf(adminui): pooled DbContext factory; role-grants reads per-call, not per-circuit

src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Historian/ContinuousHistorizationRecorder.cs

@@ -240,6 +240,7 @@ public sealed class ContinuousHistorizationRecorder : ReceiveActor, IWithTimers
         _maxWriteAttempts = maxWriteAttempts > 0 ? maxWriteAttempts : 1;
 
         ReceiveAsync<VirtualTagActor.DependencyValueChanged>(OnValueChangedAsync);
+        ReceiveAsync<VirtualTagActor.DependencyValueBatch>(OnValueBatchAsync);
         Receive<UpdateHistorizedRefs>(OnUpdateHistorizedRefs);
         Receive<DrainTick>(_ => OnDrainTick());
         Receive<DrainResult>(OnDrainResult);
@@ -275,6 +276,30 @@ public sealed class ContinuousHistorizationRecorder : ReceiveActor, IWithTimers
         base.PostStop();
     }
 
+    /// <summary>
+    ///     The mux's batched delivery: one message carrying this recorder's whole matched slice of a driver
+    ///     burst. Each item is appended by the existing per-value handler, in order — the saving here is the
+    ///     mailbox hop, not the append (a genuinely batched append is a later change).
+    ///     <para>
+    ///         ⚠️ The await below deliberately does NOT use <c>ConfigureAwait(false)</c>. <see
+    ///         cref="OnValueChangedAsync"/> reads <c>Self</c> before its own first await, so it must start
+    ///         each item ON the actor thread; a context-dropping await here would leave item 2 onward with
+    ///         no ActorContext and throw <c>NotSupportedException</c> — the Gitea #491 failure, which
+    ///         supervision turns into a restart that silently discards every historized ref. A plain await
+    ///         resumes on Akka's ActorTaskScheduler context, so the context is restored before the next
+    ///         iteration.
+    ///     </para>
+    /// </summary>
+    /// <param name="msg">The batch of matched dependency values.</param>
+    private async Task OnValueBatchAsync(VirtualTagActor.DependencyValueBatch msg)
+    {
+        IReadOnlyList<VirtualTagActor.DependencyValueChanged> items = msg.Items;
+        for (int i = 0; i < items.Count; i++)
+        {
+            await OnValueChangedAsync(items[i]);
+        }
+    }
+
     private async Task OnValueChangedAsync(VirtualTagActor.DependencyValueChanged msg)
     {
         // The mux fans values keyed by the driver ref (msg.TagId == the mux ref). Only historize refs we