R1.3 GetServerTimeZoneAsync over gRPC (live-verified); R1.4 bounded out on gRPC

Live-probed both R1.3 and R1.4 against a real 2023 R2 server over the gRPC
StatusService; implemented the one that carries an evidence-backed value.

R1.3 GetServerTimeZoneAsync — SHIPPED:
- StatusService.GetSystemTimeZoneName(uiHandle) returns the real server zone
  over RemoteGrpc (the 2020 WCF op is a client-side stub returning empty).
- HistorianGrpcStatusClient.GetSystemTimeZoneNameAsync -> dialect routing ->
  public HistorianClient.GetServerTimeZoneAsync. Non-gRPC transports fail
  closed with ProtocolEvidenceMissingException (no empty-string lie).
- Golden message-shape unit test + non-gRPC guardrail unit test + gated live
  test. 271 unit tests pass.

R1.4 GetHistorianInfoAsync (EventStorageMode) — bounded out on gRPC too:
- gRPC GetHistorianInfo is the same named-value query as 2020 WCF (only
  HistorianVersion resolves); EventStorageMode + 7 variants fail on both
  GetHistorianInfo and GetSystemParameter. The 518-byte struct is filled by a
  native vtable+648 HCAL call, not the gRPC op (per the 2023 R2 decompile), so
  the field is never on the wire. Not shipped on any transport. Closes the
  roadmap's open "build against a live 2023 R2 server" caveat.

Also correct the stale M3 roadmap section: D2 already proved
Transaction.AddNonStreamValues* rides the storage-engine pipe (STransactPipeClient2
-> aaStorageEngine), not WCF — same wall as R4.2 — so M3-over-WCF is blocked, not
"the path that is NOT the gated cache push".

Docs: hcal-roadmap.md, wcf-historian-info.md, wcf-status-localhost.md.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01B6mcaT2PjRFKcogzp9UkfC

docs/reverse-engineering/wcf-historian-info.md

@@ -1,10 +1,13 @@
 # GetHistorianInfo over 2020 WCF — GETHI is named-value-only (HCAL R1.4)
 
-**Status: ⚠ Bounded out on 2020 WCF (2026-06-20).** `GetHistorianInfoAsync` is **not shipped**:
-the one field that motivates it — `EventStorageMode` — is **not on the 2020 WCF wire**. The
-version field that GETHI *does* return over WCF is already exposed (`ProbeAsync`,
-`GetRuntimeParameterAsync("HistorianVersion")`), so there is nothing new to ship here without a
-2023 R2 gRPC server. This parallels R1.3 (`GetServerTimeZone`), which is likewise 2023R2-only.
+**Status: ⛔ Bounded out on BOTH 2020 WCF and 2023 R2 gRPC (2026-06-20; gRPC live-confirmed
+2026-06-21).** `GetHistorianInfoAsync` is **not shipped on any transport**: the one field that
+motivates it — `EventStorageMode` — is **not on the wire** on either transport (it lives only in
+the C++ HCAL's in-memory 518-byte struct, filled via a native vtable+648 call — see the §gRPC
+conclusion below). The version field GETHI *does* return is already exposed (`ProbeAsync`,
+`GetRuntimeParameterAsync("HistorianVersion")`), so there is nothing new to ship. Note: R1.3
+(`GetServerTimeZone`) — once paired with this as "2023R2-only" — **diverged**: it returns a real
+value over gRPC and **shipped** 2026-06-21 (`GetServerTimeZoneAsync`); R1.4 did not.
 
 ## What the capture showed
 
@@ -56,9 +59,19 @@ replay cannot observe or reproduce.
 - **2020 WCF:** `GetHistorianInfoAsync` would add nothing over existing surface (version only) and
   could not report a real `EventStorageMode` — so it is intentionally **not shipped** (no hollow
   `Unsupported`-returning API; project discipline: don't ship misleading behavior).
-- **2023 R2 gRPC:** `Status.GetHistorianInfo` returns the full 518-byte `btHistorianInfo`; decode
-  version@0 + `EventStorageMode`@514 there. Build + verify against a live 2023 R2 server. The
-  `HistorianInfo` / `HistorianEventStorageMode` public types should land alongside that path.
+- **2023 R2 gRPC — LIVE-PROBED 2026-06-21, also bounded out.** The earlier expectation that
+  `Status.GetHistorianInfo` returns the full 518-byte `btHistorianInfo` over gRPC was **wrong**. On
+  the real 2023 R2 server (History iface 12), the gRPC `GetHistorianInfo` is the
+  **same named-value query** as 2020 WCF: only `HistorianVersion` resolves (→ `"23,1,000,000"` +
+  `02 00 01 00` trailer); `EventStorageMode` and seven name variants return `success=false` on
+  **both** `GetHistorianInfo` and `GetSystemParameter`. The 518-byte struct is **not on the gRPC
+  wire** — the 2023 R2 decompile confirms managed `HistorianAccess.GetHistorianInfo` fills it via a
+  **native vtable+648 HCAL call** (`IClientCommon*` + offset 648), not the gRPC op, so
+  `EventStorageMode` is derived inside the C++ HCAL outside the wire on gRPC exactly as on WCF.
+  **Conclusion: `GetHistorianInfoAsync` is not shipped on any transport** (the only wire-reachable
+  field, version, is already exposed). No `HistorianInfo` / `HistorianEventStorageMode` public type
+  was added. Probe: the (now-deleted) `GrpcStatusInfoProbeTests`; raw dump under
+  `artifacts/reverse-engineering/grpc-status-info-probe/` (gitignored).
 
 ## Tooling kept as RE aids
 

docs/reverse-engineering/wcf-status-localhost.md

@@ -99,3 +99,19 @@ deliverable as server ops on 2020.** The only 2020 route to the timezone is a SQ
 mechanism than the roadmap's `Status.GetSystemTimeZoneName`. `EventStorageMode` has no 2020
 representation at all (it is a 2023 R2 event-storage-architecture field). Deliver both only against a
 live 2023 R2 gRPC server.
+
+## Resolution against the live 2023 R2 gRPC server (2026-06-21) — the two diverged
+
+Both ops were taken to the real 2023 R2 box (History iface 12) over the gRPC
+StatusService:
+
+- **R1.3 `GetServerTimeZoneAsync` — SHIPPED.** `StatusService.GetSystemTimeZoneName(uiHandle)`
+  returns the real Windows zone name **"Eastern Daylight Time"** (the 2020 stub returned empty).
+  `HistorianClient.GetServerTimeZoneAsync` routes over `RemoteGrpc`; the non-gRPC transports throw
+  `ProtocolEvidenceMissingException` (fail-closed, no empty-string lie). Golden message-shape +
+  non-gRPC guardrail unit tests + gated live test.
+- **R1.4 `GetHistorianInfoAsync` (`EventStorageMode`) — bounded out on gRPC too.** Over gRPC,
+  `GetHistorianInfo` is the **same named-value query** as 2020 WCF (only `HistorianVersion`
+  resolves); `EventStorageMode` + 7 variants fail on both `GetHistorianInfo` and
+  `GetSystemParameter`. The 518-byte struct is C++-HCAL-internal (native vtable+648), not on the
+  wire. Not shipped on any transport. See `wcf-historian-info.md`.