feat(centralui+dcl): Test Bindings popup — one-shot live read of bound tags

Adds a Test Bindings button to the Connection Bindings table on the Configure
Instance page that opens a modal showing the live current value of every bound
attribute. Reuses the routing path that the OPC UA tag browser landed on:

  Central:  TestBindingsDialog → IBindingTester → CommunicationService
            → ReadTagValuesCommand → SiteEnvelope (Ask)
  Site:     SiteCommunicationActor → DeploymentManagerActor singleton
            → DataConnectionManagerActor → child DataConnectionActor
            → _adapter.ReadBatchAsync

Split mirrors the browse handler:
  • Manager owns ConnectionNotFound (only it sees the per-site connection set).
  • Child owns ConnectionNotConnected (pre-call status check, never stash —
    read is interactive design-time), Timeout (OperationCanceledException),
    ServerError (any other exception). Per-tag failures from ReadBatchAsync
    become failure TagReadOutcomes without aborting the batch.

CentralUI:
  • IBindingTester / BindingTester — Design-role guard via HasClaim against
    JwtTokenService.RoleClaimType (not IsInRole — see c1e16cf), typed
    transport-failure translation.
  • TestBindingsDialog — ShowAsync(siteId, rows, instanceLabel) method-arg
    pattern (no Razor parameter race; see 2c138b6), groups rows by connection
    and issues one ReadAsync per connection in parallel, per-row error subline
    + per-connection banner, Refresh button re-issues the reads.
  • InstanceConfigure.razor — Test Bindings button next to Save Bindings,
    disabled when no testable rows. OPC UA only today (other protocols have
    no ReadTagValuesCommand wiring yet).

Tests:
  • Commons: ReadTagValuesCommand discovered by ManagementCommandRegistry.
  • DataConnectionLayer: unknown connection → ConnectionNotFound,
    not-connected adapter → ConnectionNotConnected (ReadBatchAsync NOT called),
    success-path mapping (Good/Bad + per-tag error), cancellation → Timeout.
  • CentralUI: register IBindingTester (and the previously-missing
    IOpcUaBrowseService) on the existing InstanceConfigureAuditDrillinTests
    Bunit container so the page renders cleanly with the new dialog.

src/ZB.MOM.WW.ScadaBridge.Communication/Actors/SiteCommunicationActor.cs

@@ -154,6 +154,12 @@ public class SiteCommunicationActor : ReceiveActor, IWithTimers
         // to its own /user/dcl-manager, which DOES have the connection.
         Receive<BrowseOpcUaNodeCommand>(msg => _deploymentManagerProxy.Forward(msg));
 
+        // Test Bindings (interactive design-time read) — same routing rationale
+        // as BrowseOpcUaNodeCommand above: the singleton always lands on the
+        // active site node, which is the node that owns the DataConnectionActor
+        // children holding the live OPC UA sessions.
+        Receive<ReadTagValuesCommand>(msg => _deploymentManagerProxy.Forward(msg));
+
         // Pattern 7: Remote Queries
         Receive<EventLogQueryRequest>(msg =>
         {

src/ZB.MOM.WW.ScadaBridge.Communication/CommunicationService.cs

@@ -370,6 +370,30 @@ public class CommunicationService
             envelope, _options.QueryTimeout, cancellationToken);
     }
 
+    // ── Test Bindings (one-shot live read of bound tags) ──
+
+    /// <summary>
+    /// Asks a site to read the current value of one or more tags on the live
+    /// server backing the given data connection. Used by the CentralUI "Test
+    /// Bindings" dialog on the Configure Instance page. The Ask is bounded by
+    /// <see cref="CommunicationOptions.QueryTimeout"/> — same latency budget
+    /// as <see cref="BrowseOpcUaNodeAsync"/> (both are interactive one-shot
+    /// design-time queries).
+    /// </summary>
+    /// <param name="siteId">The target site identifier.</param>
+    /// <param name="command">The read-tag-values command (connection name + tag paths).</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>The read result — per-tag outcomes plus an optional connection-level failure.</returns>
+    public Task<ReadTagValuesResult> ReadTagValuesAsync(
+        string siteId,
+        ReadTagValuesCommand command,
+        CancellationToken cancellationToken = default)
+    {
+        var envelope = new SiteEnvelope(siteId, command);
+        return GetActor().Ask<ReadTagValuesResult>(
+            envelope, _options.QueryTimeout, cancellationToken);
+    }
+
     // ── Pattern 8: Heartbeat (site→central, Tell) ──
     // Heartbeats are received by central, not sent. No method needed here.