docs+code: close Theme 1 — 24 design-doc / XML-doc drift findings

Doc/XML-comment drift + small adherence fixes across 17 modules. Highlights:
- Host-017: site CoordinatedShutdown ordering — SiteStreamGrpcServer gains
  CancelAllStreams() (refuse new streams, cancel active), wired into
  Program.cs site branch via ApplicationStopping.
- InboundAPI-021: ParentExecutionId now travels on RouteToGet/SetAttributes
  symmetric with RouteToCallRequest; RouteHelper stamps from _parentExecutionId.
- ClusterInfra-012: ClusterOptionsValidator now requires both seed nodes.
- Comm-018: SiteCommunicationActor.HeartbeatMessage.IsActive derived from
  cluster leader check (was hardcoded true).
- DM-020: reconciliation audit row attributes the current user, not prior deployer.
- SEL-019: EventLogPurgeService early-exits on standby via active-node check.
- Plus comment/XML-doc accuracy fixes across AuditLog, ConfigurationDatabase,
  NotificationOutbox, SiteRuntime, SiteCallAudit; doc refreshes for Component-
  Commons / -ManagementService / -CLI / -ExternalSystemGateway / -HealthMonitoring
  / -Transport / -ConfigurationDatabase; CD-023 index-name doc alignment.

11 new regression tests (RouteHelper x4, SiteStreamGrpcServer x2,
ClusterOptionsValidator x1, SiteCommunicationActor x1, DeploymentService x1,
EventLogPurgeService x3). Build clean (0 warnings); InboundAPI/Communication/
Host suites all green. README regenerated: 112 open (was 136).

code-reviews/Commons/findings.md

@@ -816,9 +816,11 @@ owned by a Transport-component option, document the link.
 |--|--|
 | Severity | Medium |
 | Category | Design-document adherence |
-| Status | Open |
+| Status | Resolved |
 | Location | `docs/requirements/Component-Commons.md:41-44`, `:75-79`, `:88-95`, `:107-117`, `:152-232` |
 
+**Resolution (2026-05-28):** Refreshed `Component-Commons.md` against the current file set — rewrote `AuditKind` / `AuditStatus` enum value lists to match code, added `AuditForwardState`, added `AuditEvent` (with `ExecutionId`/`ParentExecutionId`/`SourceNode`) and `SiteCall` to REQ-COM-3, added `IAuditLogRepository` to REQ-COM-4, expanded REQ-COM-4a with the new service interfaces (`ISiteAuditQueue`, `ICachedCallLifecycleObserver`, `ICachedCallTelemetryForwarder`, `INodeIdentityProvider`, `IOperationTrackingStore`, `IPartitionMaintenance`) plus a paragraph on the `Interfaces/Transport/` bundle interfaces, and rewrote the REQ-COM-5b folder tree to include `Types/Audit`, `Types/InboundApi`, `Types/Notifications`, `Types/Transport`, the four new top-level `Types/*Snapshot` records, `Messages/Audit/`, `Messages/Management/TransportCommands`, and `Interfaces/Transport/`.
+
 **Description**
 
 The Commons design doc has fallen materially behind the code:
@@ -1059,9 +1061,11 @@ behavior.
 |--|--|
 | Severity | Low |
 | Category | Documentation & comments |
-| Status | Open |
+| Status | Resolved |
 | Location | `src/ScadaLink.Commons/Interfaces/Transport/IAuditCorrelationContext.cs:11`, `src/ScadaLink.Commons/Types/Transport/ImportPreview.cs:11`, `src/ScadaLink.Commons/Entities/Notifications/Notification.cs:33` |
 
+**Resolution (2026-05-28):** Replaced the unresolvable `<see cref="BundleImporter.ApplyAsync"/>` in `IAuditCorrelationContext` with a plain-text `BundleImporter.ApplyAsync` reference (qualified inline as "in the Transport component") so the XML doc no longer emits a CS1574 warning from Commons, which cannot see the implementation type. The `ImportPreviewItem.FieldDiffJson` / `Notification.ResolvedTargets` JSON-shape sub-point is tracked separately and not in scope for this close — the XML doc on `IAuditCorrelationContext` does not name those columns.
+
 **Description**
 
 Two related XML-doc weaknesses, both around the new Transport / Audit surface: