feat: OPC UA address-space search plumbing — actor + comm + BrowseService (T15)

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

@@ -371,6 +371,28 @@ public class CommunicationService
             envelope, _options.QueryTimeout, cancellationToken);
     }
 
+    /// <summary>
+    /// Asks a site to run a bounded recursive search of the address space on the
+    /// live server backing the given data connection. The address-space analogue
+    /// of <see cref="BrowseNodeAsync"/> — used by the CentralUI OPC UA tag picker's
+    /// "find a tag" box. The Ask is bounded by <see cref="CommunicationOptions.QueryTimeout"/>,
+    /// the same latency budget as browse and the other interactive design-time
+    /// queries.
+    /// </summary>
+    /// <param name="siteId">The target site identifier.</param>
+    /// <param name="command">The address-space search command (connection name + query + depth/result caps).</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>The search result (matches + cap-reached flag + structured failure).</returns>
+    public Task<SearchAddressSpaceResult> SearchAddressSpaceAsync(
+        string siteId,
+        SearchAddressSpaceCommand command,
+        CancellationToken cancellationToken = default)
+    {
+        var envelope = new SiteEnvelope(siteId, command);
+        return GetActor().Ask<SearchAddressSpaceResult>(
+            envelope, _options.QueryTimeout, cancellationToken);
+    }
+
     // ── Test Bindings (one-shot live read of bound tags) ──
 
     /// <summary>