docs(alarms): describe the real StreamAlarms open sequence, and close TST-16

The final integration review's non-blocker reservations, all documentation
or comment truth except one test arm.

The alarm feed opens provider_status -> snapshot_status -> cached
active_alarm -> snapshot_complete, which is what GatewayAlarmMonitor has
done since the snapshot_status frame landed. Two places still described
the old order: docs/Grpc.md said provider_status arrived *after* the
initial snapshot, contradicting its own snapshot_status section two
paragraphs down, and AlarmFeedMessage's leading proto comment named
neither status frame at all. Both now state the sequence the monitor
emits, so a client author reading either one gets the frame order right.

The proto comment change flows through the generated trees (Contracts,
Go, Java) and the client descriptor set; the Rust vendored copy stays
byte-identical to canonical. Python's generator does not carry proto
comments into its output, so it has no delta.

AlarmsHubPublisherTests' valueless-payload case covered snapshot_complete
and provider_status but not snapshot_status, leaving the newest arm
unpinned against the redaction switch that must ignore it. Added.

WnWrapAlarmConsumer's ack comment led with the 2026-05-01 reading that
-55 tracks the 8-arg overload, then refuted itself six lines later with
the 2026-08-18 probe. It now leads with the observation labelled as
narrower than it reads -- mirroring the correction already in
docs/AlarmClientDiscovery.md -- so the block argues one thing: the 6-arg
call site stays for parity, and rc semantics are per the probe. A
paragraph orphaned by an earlier splice is rewrapped. Comment interior
only; the file compiles on Windows.

TST-16 gets a dated closure note rather than a rewrite: the flag it
called dead was implemented 2026-08-18. GatewayDashboardDesign's /browse
paragraph gains the failed-read carve-out GatewayConfiguration already
documented, so the two agree that a failed read keeps its - placeholder.

archreview/remediation/60-testing-docs-gaps.md

@@ -355,6 +355,8 @@ If TST-02's interim mitigation (flip retention off) is chosen instead of impleme
 
 **Verification.** `dotnet build src/ZB.MOM.WW.MxGateway.Server`; test toggling the flag suppresses/shows values; docs match.
 
+**Closed 2026-08-18 — implemented (the Design's recommended path).** The flag is no longer dead: it now gates value display on all three seams that carry a tag value. `Dashboard/DashboardLiveDataService.cs` substitutes `[redacted]` at the service boundary for each successfully read `/browse` tag (a failed read keeps its `-` placeholder, so the error row and the redaction cannot contradict each other); `Dashboard/Hubs/AlarmsHubPublisher.cs` clears `current_value`/`limit_value` from a **deep-cloned** `AlarmFeedMessage` before broadcasting to `/hubs/alarms`, and `DashboardEventBroadcaster` does the same for the events-hub mirror — clones, because the sources fan out to gRPC `StreamAlarms`/`StreamEvents` and the replay ring, so no gRPC client is affected by this dashboard-display flag. The flag is **kept**, default still `false`. The stale prose the Finding flagged is gone: `docs/GatewayConfiguration.md` and `docs/GatewayDashboardDesign.md` now describe the real behaviour. Status tracked in `00-tracking.md` (already **Done**).
+
 ---
 
 ## TST-17 — Vendor-gated alarm parity residuals silently lossy   `Medium` · `—`