Remove project bookkeeping citations from shipped code comments across the
solution: hyphenated task IDs (WP-14, StoreAndForward-025), milestone/task/
issue refs (M3, Task 4, Audit Log #23, #21), Bundle X task-bundle labels,
and C/D/K/S/T phase labels.
Comment text only — no code logic, string/log literals, or XML-doc structure
changed. Genuine descriptions are preserved (only the citation is stripped),
and technical lookalikes are retained (UTF-8, SHA-256, T00:00:00, M365,
UTC-5, pre-C4/pre-C5 schema versions). Flagged by the new CommentChecker
TaskReferenceInComment / TrackingReferenceInComment checks plus targeted
grep passes; full solution builds clean, append-only guard tests pass.
- Remove redundant linked CancellationTokenSource in ProbeAsync; pass the
framework cancellationToken and ProbeTimeout directly to Ask (the two-CTS
pattern was redundant — Ask already honours both the timeout and the token).
- Add EchoActor XML <remarks> explaining why no Receive<Identify> handler is
needed (ActorBase answers Identify automatically).
- Add PreCancelledToken_ReportsUnhealthy_DoesNotThrow test: verifies the
never-throws guarantee on the shutdown-race path (token already cancelled
before CheckHealthAsync is invoked).
REQ-HOST-4a lists "required cluster singletons running (if applicable)" as a
readiness criterion, but /health/ready only checked database + akka-cluster.
Add a third Ready-tagged check, RequiredSingletonsHealthCheck, registered in the
Central-role AddHealthChecks() chain (so it is naturally role-scoped — site nodes
never run it).
Probe: for each required central singleton, Ask its local ClusterSingletonProxy
an Identify with a short bounded per-singleton timeout (~2s, probes run
concurrently via Task.WhenAll). A non-null ActorIdentity.Subject within the
timeout means the singleton is running and reachable through the proxy; a null
subject or a timeout means unreachable → Unhealthy, naming the unreachable
singleton(s). The check never throws (catch-all → Unhealthy) and resolves
ActorSystem lazily from DI per probe (Unhealthy if Akka not yet up).
Required-always set = the five singleton proxies created unconditionally in
AkkaHostedService.RegisterCentralActors: notification-outbox, audit-log-ingest,
site-call-audit, audit-log-purge, site-audit-reconciliation. There are no
feature/config-gated central singletons today; any future gated singleton is the
"if applicable" case and must NOT be added to the required set.
Leadership-agnostic: the proxy reaches the singleton from either central node, so
a ready standby still reports ready (readiness must not require cluster
leadership — that is the Active tier's job). During a brief singleton handover the
probe may time out and the node flaps to not-ready, which is correct (a node
mid-handover is legitimately not fully ready); no retries, to keep the probe fast.
Tests (TDD): RequiredSingletonsHealthCheckTests exercises the probe against a
TestKit ActorSystem — all proxies present+reachable → Healthy; one missing →
Unhealthy naming it; ActorSystem absent → Unhealthy, no throw. HealthCheckTests
regression-guards the Ready tag + absence of the Active tag on the new check.
Resolve all 622 issues flagged by the enhanced CommentChecker: add missing
<returns> tags (incl. the standard phrasing on non-generic Task methods),
add missing <summary> tags, and replace misused/redundant <inheritdoc/> on
members that override or implement nothing with real documentation.
Documentation-only — no behavior change; solution builds clean.
Joseph Doherty