refactor(comm): retire ClusterClient naming after the gRPC cutover

Phase 4 of the ClusterClient -> gRPC migration deleted the Akka transports
but left the naming behind: `ClusterClientSiteAuditClient` was transport-
agnostic and worked unchanged, so it survived the deletion under a name
that now describes a transport the repo no longer has. Same for a scatter
of doc-comments still framing gRPC as "the new transport" beside an Akka
one that is gone.

Renames it to `SiteCommunicationAuditClient` (and its test file) and
rewrites the stale comments to describe the single transport that exists.
Also tightens CLAUDE.md: drops the self-describing directory listing and
the 27-component enumeration in favour of the non-obvious parts only.

Behaviour-neutral: names and prose only. Recorded as the Phase 4
follow-up in docs/plans/2026-07-22-clusterclient-to-grpc-plan.md.

src/ZB.MOM.WW.ScadaBridge.Commons/Entities/Sites/Site.cs

@@ -10,9 +10,9 @@ public class Site
     public string SiteIdentifier { get; set; }
     /// <summary>Optional description of the site.</summary>
     public string? Description { get; set; }
-    /// <summary>Akka remote address for site node A (ClusterClient contact point).</summary>
+    /// <summary>Akka remote address for site node A.</summary>
     public string? NodeAAddress { get; set; }
-    /// <summary>Akka remote address for site node B (ClusterClient contact point).</summary>
+    /// <summary>Akka remote address for site node B.</summary>
     public string? NodeBAddress { get; set; }
     /// <summary>gRPC endpoint for site node A used by the central SiteStreamGrpcClient.</summary>
     public string? GrpcNodeAAddress { get; set; }