feat(dcl+ui): rename BrowseOpcUaNode -> ConnectionName-keyed; implement site handler + dialog failure mapping

- BrowseOpcUaNodeCommand: int DataConnectionId -> string ConnectionName
  (site DataConnectionManagerActor indexes children by name; CentralUI
  already has the connection name in scope via the dropdown — no extra
  plumbing across the trust boundary).
- IOpcUaBrowseService / OpcUaBrowseService: parameter renamed accordingly.
- OpcUaBrowserDialog: collapse the duplicate ConnectionName parameters
  (display label and routing key are the same string).
- Task 10: DataConnectionManagerActor forwards BrowseOpcUaNodeCommand to
  its child by name (owns ConnectionNotFound); DataConnectionActor adds
  the receive across all three lifecycle states (Connecting / Connected
  / Reconnecting) and maps adapter outcomes to BrowseFailureKind
  (NotBrowsable / ConnectionNotConnected / Timeout / ServerError).
- Task 17: SetFailure in OpcUaBrowserDialog implements the full
  BrowseFailureKind switch with friendly UI messages.
- Tests: DataConnectionManagerBrowseHandlerTests covers ConnectionNotFound,
  NotBrowsable, success, and ConnectionNotConnectedException paths.

src/ZB.MOM.WW.ScadaBridge.CentralUI/Services/IOpcUaBrowseService.cs

@@ -21,17 +21,17 @@ public interface IOpcUaBrowseService
 {
     /// <summary>
     /// Enumerates the immediate children of an OPC UA node on the live server
-    /// backing <paramref name="dataConnectionId"/> at <paramref name="siteId"/>.
+    /// backing <paramref name="connectionName"/> at <paramref name="siteId"/>.
     /// Pass <c>null</c> for <paramref name="parentNodeId"/> to browse from the
     /// server root (ObjectsFolder).
     /// </summary>
     /// <param name="siteId">The target site identifier.</param>
-    /// <param name="dataConnectionId">Id of the site-local data connection to browse against.</param>
+    /// <param name="connectionName">Name of the site-local data connection to browse against — the site's <c>DataConnectionManagerActor</c> indexes its children by name.</param>
     /// <param name="parentNodeId">Node to browse, or <c>null</c> to browse from the server root.</param>
     /// <param name="cancellationToken">Cancellation token.</param>
     Task<BrowseOpcUaNodeResult> BrowseChildrenAsync(
         string siteId,
-        int dataConnectionId,
+        string connectionName,
         string? parentNodeId,
         CancellationToken cancellationToken = default);
 }

src/ZB.MOM.WW.ScadaBridge.CentralUI/Services/OpcUaBrowseService.cs

@@ -37,7 +37,7 @@ public sealed class OpcUaBrowseService : IOpcUaBrowseService
     /// <inheritdoc/>
     public async Task<BrowseOpcUaNodeResult> BrowseChildrenAsync(
         string siteId,
-        int dataConnectionId,
+        string connectionName,
         string? parentNodeId,
         CancellationToken cancellationToken = default)
     {
@@ -56,7 +56,7 @@ public sealed class OpcUaBrowseService : IOpcUaBrowseService
         {
             return await _communication.BrowseOpcUaNodeAsync(
                 siteId,
-                new BrowseOpcUaNodeCommand(dataConnectionId, parentNodeId),
+                new BrowseOpcUaNodeCommand(connectionName, parentNodeId),
                 cancellationToken);
         }
         catch (TimeoutException ex)