Implement LmxOpcUa server — all 6 phases complete

Full OPC UA server on .NET Framework 4.8 (x86) exposing AVEVA System
Platform Galaxy tags via MXAccess. Mirrors Galaxy object hierarchy as
OPC UA address space, translating contained-name browse paths to
tag-name runtime references.

Components implemented:
- Configuration: AppConfiguration with 4 sections, validator
- Domain: ConnectionState, Quality, Vtq, MxDataTypeMapper, error codes
- MxAccess: StaComThread, MxAccessClient (partial classes), MxProxyAdapter
  using strongly-typed ArchestrA.MxAccess COM interop
- Galaxy Repository: SQL queries (hierarchy, attributes, change detection),
  ChangeDetectionService with auto-rebuild on deploy
- OPC UA Server: LmxNodeManager (CustomNodeManager2), LmxOpcUaServer,
  OpcUaServerHost with programmatic config, SecurityPolicy None
- Status Dashboard: HTTP server with HTML/JSON/health endpoints
- Integration: Full 14-step startup, graceful shutdown, component wiring

175 tests (174 unit + 1 integration), all passing.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tools/opcuacli-dotnet/README.md

@@ -0,0 +1,123 @@
+# OPC UA CLI Tool (.NET)
+
+Command-line utility for testing OPC UA server functions. Built with the [OPC Foundation UA .NET Standard](https://github.com/OPCFoundation/UA-.NETStandard) client library and [CliFx](https://github.com/Tyrrrz/CliFx).
+
+- **Runtime**: .NET 10
+- **OPC UA Client**: OPCFoundation.NetStandard.Opc.Ua.Client
+
+## Build & Run
+
+```bash
+cd tools/opcuacli-dotnet
+dotnet build
+dotnet run -- <command> [options]
+```
+
+## Commands
+
+### connect
+
+Test connection to an OPC UA server:
+
+```
+dotnet run -- connect -u opc.tcp://localhost:4840
+```
+
+| Flag | Description |
+|------|-------------|
+| `-u` | OPC UA server endpoint URL (required) |
+
+### read
+
+Read a value from a node:
+
+```
+dotnet run -- read -u opc.tcp://localhost:4840 -n "ns=2;s=MyNode"
+```
+
+| Flag | Description |
+|------|-------------|
+| `-u` | OPC UA server endpoint URL (required) |
+| `-n` | Node ID to read (required) |
+
+### write
+
+Write a value to a node (auto-detects the data type from the current value):
+
+```
+dotnet run -- write -u opc.tcp://localhost:4840 -n "ns=2;s=MyNode" -v 42
+```
+
+| Flag | Description |
+|------|-------------|
+| `-u` | OPC UA server endpoint URL (required) |
+| `-n` | Node ID to write to (required) |
+| `-v` | Value to write (required) |
+
+### subscribe
+
+Monitor a node for value changes:
+
+```
+dotnet run -- subscribe -u opc.tcp://localhost:4840 -n "ns=2;s=MyNode" -i 500
+```
+
+| Flag | Description |
+|------|-------------|
+| `-u` | OPC UA server endpoint URL (required) |
+| `-n` | Node ID to monitor (required) |
+| `-i` | Polling interval in milliseconds (default: 1000) |
+
+### browse
+
+Browse the OPC UA address space:
+
+```bash
+# Browse top-level Objects folder
+dotnet run -- browse -u opc.tcp://localhost:4840
+
+# Browse a specific node
+dotnet run -- browse -u opc.tcp://localhost:4840 -n "ns=2;s=MyFolder"
+
+# Browse recursively (depth 3)
+dotnet run -- browse -u opc.tcp://localhost:4840 -r -d 3
+```
+
+| Flag | Description |
+|------|-------------|
+| `-u` | OPC UA server endpoint URL (required) |
+| `-n` | Node ID to browse (default: Objects folder) |
+| `-d` | Maximum browse depth (default: 1) |
+| `-r` | Browse recursively using `--depth` as max depth |
+
+## Example: Testing the LmxOpcUa Server
+
+```bash
+cd tools/opcuacli-dotnet
+
+# Connect to the local OPC UA server
+dotnet run -- connect -u opc.tcp://localhost:4840
+
+# Browse the address space
+dotnet run -- browse -u opc.tcp://localhost:4840 -r -d 3
+
+# Read a tag value
+dotnet run -- read -u opc.tcp://localhost:4840 -n "ns=2;s=TestMachine_001.SomeAttribute"
+
+# Subscribe to live updates
+dotnet run -- subscribe -u opc.tcp://localhost:4840 -n "ns=2;s=TestMachine_001.SomeAttribute" -i 500
+```
+
+## Example: Testing with the OPC PLC Sample Server
+
+```bash
+# Start the sample server (from another terminal)
+cd tools/opcsampleserver/publish
+dotnet opcplc.dll --pn=50000 --autoaccept --unsecuretransport
+
+# Browse the sample server
+dotnet run -- browse -u opc.tcp://localhost:50000 -r -d 2
+
+# Read a sample node
+dotnet run -- read -u opc.tcp://localhost:50000 -n "ns=2;s=SlowUInt1"
+```