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/InboundAPI/findings.md

@@ -8,7 +8,7 @@
 | Last reviewed | 2026-05-28 |
 | Reviewer | claude-agent |
 | Commit reviewed | `1eb6e97` |
-| Open findings | 8 |
+| Open findings | 7 |
 
 ## Summary
 
@@ -1017,7 +1017,7 @@ regression test posting with `application/JSON` and Transfer-Encoding: chunked.
 |--|--|
 | Severity | Medium |
 | Category | Design-document adherence |
-| Status | Open |
+| Status | Resolved |
 | Location | `src/ScadaLink.InboundAPI/RouteHelper.cs:141-143`, `:182-183`, `:225-226`; `src/ScadaLink.Commons/Messages/InboundApi/RouteToInstanceRequest.cs:15-21`, `:36-40`, `:55-59` |
 
 **Description**
@@ -1055,6 +1055,25 @@ from `_parentExecutionId` in `RouteTarget.GetAttributes` and
 their emitted audit rows. Add a `RouteHelperTests` regression case asserting
 that an attribute read/write carries the inherited `ParentExecutionId`.
 
+**Resolution (2026-05-28):**
+
+Wire fix landed — `RouteToGetAttributesRequest` and `RouteToSetAttributesRequest`
+now carry a trailing additive `Guid? ParentExecutionId = null`, mirroring
+`RouteToCallRequest`; `RouteTarget.GetAttributes` and `RouteTarget.SetAttributes`
+stamp `_parentExecutionId` onto the request, so the field travels off the
+inbound API box symmetrically across all three `Route.To()` verbs. Four
+regression tests added to `RouteHelperTests` (with/without parent id for both
+verbs).
+
+Site-side audit emission for routed reads/writes is NOT currently wired —
+`DeploymentManagerActor.RouteInboundApiGetAttributes` / `…SetAttributes` and
+`InstanceActor.HandleGetAttribute` / `HandleSetStaticAttribute` /
+`HandleSetDataAttribute` do not call `IAuditWriter` today (only script-driven
+`AuditingDbConnection` / `AuditingDbCommand` paths emit audit rows on the site
+side). The `ParentExecutionId` is now available on the wire so once those
+audit emissions land (tracked separately under the Audit Log site-wiring
+backlog), they can stamp the parent id without any further plumbing.
+
 ### InboundAPI-022 — `IActiveNodeGate` has no production registration in Host — standby-node gating is silently disabled in production
 
 | | |