test+docs(v3-batch4-wp5): 2-node dual-namespace harness tests + address-space docs

Tests:
- OpcUaServer.IntegrationTests/DualNamespaceAddressSpaceTests.cs (NEW, over-the-wire,
  offline-safe): both namespace URIs registered + distinct; Raw + UNS subtrees browse
  and read; UNS variable Organizes-references its raw node; single-source fan-out parity
  (identical value/quality/timestamp on both NodeIds); HistoryRead via either NodeId ->
  GoodNoData under the shared tagname; WriteOperate gate symmetric across both NodeIds.
- Host.IntegrationTests/EquipmentNamespaceMaterializationTests.cs (extended): full deploy
  -> persisted-artifact -> ParseComposition round-trip carrying both realms, sealing across
  the redundant 2-node cluster (redundancy non-interference). In-memory harness, offline.

Docs (dual-namespace reality):
- CLAUDE.md: new "v3 OPC UA Address Space (Batch 4)" section + Batch-4 testing paragraph.
- docs/Uns.md: address-space projection (two namespaces, Organizes edge, effective-name leaf).
- docs/Historian.md: dual-registration (both NodeIds -> one tagname); updated CLI examples.
- docs/ScriptedAlarms.md + docs/AlarmTracking.md: multi-notifier fan-out, ConditionId=RawPath.
- docs/ScriptEditor.md: dual-namespace clarification (script tag-path semantics unchanged).

Claude-Session: https://claude.ai/code/session_01LVneM3eh1UtJxEisFXgmox

docs/Uns.md

@@ -110,6 +110,41 @@ UNS-referenced, or named by a script literal — see [`Raw.md`](Raw.md).
 `GalaxyMxGateway` driver in `/raw`, referenced into equipment like any other raw
 tag. There is no separate alias concept or `SystemPlatform`-kind namespace.
 
+### OPC UA address-space projection (v3 Batch 4 — dual namespace)
+
+> **v3 (Batch 4):** the server now exposes the address space under **two OPC UA
+> namespaces** instead of the old single `https://zb.com/otopcua/ns`:
+>
+> | Namespace URI | Subtree | NodeId `s=` scheme |
+> |---|---|---|
+> | `https://zb.com/otopcua/raw` | the `/raw` device tree (Folder → Driver → Device → TagGroup → Tag) | the node's **RawPath** (e.g. `Plant/Modbus/dev1/Speed`) |
+> | `https://zb.com/otopcua/uns` | the UNS tree (Area → Line → Equipment → signal) | the slash-joined **`Area/Line/Equipment/EffectiveName`** |
+
+Every device value has **exactly one source** — the raw tag's node in the Raw
+namespace. A `UnsTagReference` projects that raw tag into an equipment as a
+**UNS-namespace variable** whose NodeId leaf is the reference's **effective name**
+(the display-name override else the raw tag's `Name`). The UNS variable does not
+bind a driver of its own: it carries an **`Organizes` reference to its backing raw
+node** and mirrors it. A single driver publish for a RawPath **fans out** to the
+raw NodeId AND every referencing UNS NodeId with identical value / quality /
+source-timestamp — the two NodeIds never drift.
+
+- **Reads / subscriptions** work through either NodeId and return the same data.
+- **Writes** route through either NodeId to the same backing driver ref under the
+  **same `WriteOperate` gating** (a UNS write is neither more nor less privileged
+  than the raw write it fans from); a failed device write reverts both NodeIds via
+  the shared fan-out.
+- **HistoryRead** works through either NodeId and returns the same series — both
+  NodeIds register the **same historian tagname** (see [`Historian.md`](Historian.md)).
+- **Native alarms** materialize once at the raw tag (`ConditionId = RawPath`) and
+  fan via SDK notifiers to the raw device folder AND every referencing equipment
+  folder — see [`ScriptedAlarms.md`](ScriptedAlarms.md) / [`AlarmTracking.md`](AlarmTracking.md).
+
+Note the two distinct identity strings: the wire **NodeId** is the path
+`Area/Line/Equipment/EffectiveName`, while the **effective-name uniqueness key**
+above is `{EquipmentId}/{EffectiveName}` (the logical per-equipment collision
+space the guards enforce). They are related but not the same string.
+
 ### Virtual tags
 
 A virtual tag is bound to an equipment and driven by a **script** (no driver).