docs: sync against recent code changes

Five doc-content updates after this session's code-review resolution
sweep. No code touched; pure documentation drift correction.

1. docs/reqs/HighLevelReqs.md (HLR-007 — Service Hosting):
   Refreshed the deployment description from "three cooperating
   processes (Server, Admin, Galaxy.Host)" to "two cooperating
   Windows services (Server, Admin)". The legacy x86 TopShelf
   Galaxy.Host process was retired in PR 7.2 (2026-04-30); Galaxy
   access now flows through the in-process Tier-A GalaxyDriver
   talking gRPC to the sibling mxaccessgw gateway. Also called out
   decision #30 (AddWindowsService replacing TopShelf) inline.

2. docs/VirtualTags.md:
   - Line 9: "compiled via Microsoft.CodeAnalysis.CSharp.Scripting"
     replaced with the current pipeline (Microsoft.CodeAnalysis.CSharp
     regular compiler — Core.Scripting-008 / -016 retired the
     CSharpScript/ScriptRunner path).
   - Line 39: orphan-thread leak description rewritten. The
     CSharp.Scripting-era "underlying ScriptRunner keeps running on
     its thread-pool thread until the Roslyn runtime returns" is no
     longer accurate — the new pipeline binds the script as a
     regular C# Func<> delegate, so the leak is now "synchronous
     CPU-bound work on a pool thread" (same operator-visible
     effect, different mechanism).

3. docs/v2/plan.md decision #29 ("Galaxy Host is a separate Windows
   service"):
   Annotated both the decision body and the decision-log table row
   with "Reversed PR 7.2, 2026-04-30" + a one-line summary of the
   replacement architecture. The original reasoning is preserved as
   audit trail per the decision-log convention.

4. docs/v2/implementation/phase-7-scripting-and-alarming.md A.1:
   Added an Implementation note describing the
   Core.Scripting-008 / -016 supersession of the original
   CSharpScript pipeline. The historical record stays; the note
   points future readers at docs/VirtualTags.md "Compile cache"
   for the current contract.

5. docs/plans/alarms-over-gateway.md "Files" section under client
   regeneration:
   Updated the .NET regeneration instructions to point at the new
   ZB.MOM.WW.MxGateway.Contracts.csproj path. The old
   clients/dotnet/MxGateway.Client.csproj no longer exists in the
   sibling repo (restructure after this plan was written) and the
   vendored-binaries situation in
   src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.Galaxy/libs/ is called out
   so a reader following the plan won't chase a deleted path.

Verification: grep against docs/ for the pre-fix wordings ("three
cooperating processes", "Galaxy.Host (TopShelf)", "ScriptRunner",
the wrong BadDeviceFailure hex code 0x80550000) returns no hits.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docs/reqs/HighLevelReqs.md

@@ -1,6 +1,6 @@
 # High-Level Requirements
 
-> **Revision** — Refreshed 2026-04-19 for the OtOpcUa v2 multi-driver platform (task #205). The original 2025 text described a single-process Galaxy/MXAccess server called LmxOpcUa. Today the project is the **OtOpcUa** multi-driver OPC UA platform deployed as three cooperating processes (Server, Admin, Galaxy.Host). The Galaxy integration is one of seven shipped drivers. HLR-001 through HLR-008 have been rewritten driver-agnostically; HLR-009 has been retired (the embedded Status Dashboard is superseded by the Admin UI). HLR-010 through HLR-017 are new and cover plug-in drivers, resilience, Config DB / draft-publish, cluster redundancy, fleet-wide identifier uniqueness, Admin UI, audit logging, metrics, and the Roslyn capability-wrapping analyzer.
+> **Revision** — Refreshed 2026-05-23 for the OtOpcUa v2 multi-driver platform. The original 2025 text described a single-process Galaxy/MXAccess server called LmxOpcUa. Today the project is the **OtOpcUa** multi-driver OPC UA platform deployed as two cooperating processes (Server, Admin). The Galaxy integration is one of seven shipped drivers and is now an in-process Tier-A driver that talks gRPC to a separately installed `mxaccessgw` gateway (sibling repo) — PR 7.2 (2026-04-30) retired the legacy out-of-process `Galaxy.Host` Windows service. HLR-001 through HLR-008 have been rewritten driver-agnostically; HLR-009 has been retired (the embedded Status Dashboard is superseded by the Admin UI). HLR-010 through HLR-017 cover plug-in drivers, resilience, Config DB / draft-publish, cluster redundancy, fleet-wide identifier uniqueness, Admin UI, audit logging, metrics, and the Roslyn capability-wrapping analyzer.
 
 ## HLR-001: OPC UA Server
 
@@ -28,11 +28,10 @@ Drivers whose backend has a native change signal (e.g. Galaxy's `time_of_last_de
 
 ## HLR-007: Service Hosting
 
-The system shall be deployed as three cooperating Windows services:
+The system shall be deployed as two cooperating Windows services (the legacy `OtOpcUa.Galaxy.Host` x86 host was retired in PR 7.2 — Galaxy access now flows through the separately installed `mxaccessgw` gateway, which lives in a sibling repository and is not part of the OtOpcUa deployment):
 
-- **OtOpcUa.Server** — .NET 10 x64, `Microsoft.Extensions.Hosting` + `AddWindowsService`, hosts all non-Galaxy drivers in-process and the OPC UA endpoint.
+- **OtOpcUa.Server** — .NET 10 AnyCPU, `Microsoft.Extensions.Hosting` + `AddWindowsService` (decision #30 replaced the original TopShelf choice), hosts every driver in-process — including the new Tier-A `GalaxyDriver` that speaks gRPC to `mxaccessgw` — and the OPC UA endpoint.
 - **OtOpcUa.Admin** — .NET 10 x64 Blazor Server web app, hosts the admin UI, SignalR hubs for live updates, `/metrics` Prometheus endpoint, and audit log writers.
-- **OtOpcUa.Galaxy.Host** — .NET Framework 4.8 x86 (TopShelf), hosts MXAccess COM + Galaxy Repository SQL + Historian plugin. Talks to `Driver.Galaxy.Proxy` inside `OtOpcUa.Server` via a named pipe (MessagePack over length-prefixed frames, per-process shared secret, SID-restricted ACL).
 
 ## HLR-008: Logging