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.CentralUI/Services/IBindingTester.cs

@@ -0,0 +1,39 @@
+using ZB.MOM.WW.ScadaBridge.Commons.Messages.Management;
+
+namespace ZB.MOM.WW.ScadaBridge.CentralUI.Services;
+
+/// <summary>
+/// CentralUI facade over the central-to-site "Test Bindings" read command.
+/// Backs the Test Bindings dialog on the Configure Instance page: on open and
+/// on Refresh, the dialog issues one <see cref="ReadAsync"/> per distinct
+/// connection (grouped from the page's bindings table) and renders the
+/// per-tag outcomes.
+/// </summary>
+/// <remarks>
+/// The service is the trust boundary for the read capability: it enforces the
+/// <c>Design</c> role at central before any cross-cluster traffic is
+/// generated, because site-side actors do not unwrap the central trust
+/// envelope. Transport failures (timeouts, unreachable sites) are translated
+/// into a typed <see cref="ReadTagValuesFailure"/> so the dialog can render an
+/// inline banner without crashing — same shape as
+/// <see cref="IOpcUaBrowseService"/>.
+/// </remarks>
+public interface IBindingTester
+{
+    /// <summary>
+    /// Reads the current value of one or more tags on the live server backing
+    /// <paramref name="connectionName"/> at <paramref name="siteId"/>. The
+    /// caller is expected to group its bindings by connection name and issue
+    /// one call per group (in parallel — the dialog uses
+    /// <c>Task.WhenAll</c>).
+    /// </summary>
+    /// <param name="siteId">The target site identifier.</param>
+    /// <param name="connectionName">Name of the site-local data connection — the site's <c>DataConnectionManagerActor</c> indexes its children by name.</param>
+    /// <param name="tagPaths">Tag paths to read.</param>
+    /// <param name="ct">Cancellation token.</param>
+    Task<ReadTagValuesResult> ReadAsync(
+        string siteId,
+        string connectionName,
+        IReadOnlyList<string> tagPaths,
+        CancellationToken ct = default);
+}