Wires the OPC UA Tag Browser cross-cluster path: central UI Asks via
CommunicationService.BrowseOpcUaNodeAsync -> ClusterClient -> site
SiteCommunicationActor -> /user/dcl-manager (Task 10 handler).
Uses ActorSelection.Tell(msg, Sender) since DataConnectionManagerActor
is not a child of DeploymentManagerActor and ActorSelection has no
Forward() helper; preserving Sender keeps the BrowseOpcUaNodeResult
routing back to the original Ask.
Integration test deferred: tests/ZB.MOM.WW.ScadaBridge.IntegrationTests
has no ClusterFixture (only ScadaBridgeWebApplicationFactory, which
does not expose a Communication service nor a seeded site OPC UA
connection). Round-trip will be exercised manually under Task 19.