Task #253 — E2E CLI test scripts + FOCAS test-client CLI

The driver-layer integration tests confirm the driver sees the PLC, and
the Client.CLI tests confirm the client sees the server. Nothing glued
them end-to-end until this PR.

- scripts/e2e/_common.ps1: shared helpers — CLI invocation (published-
  binary OR `dotnet run` fallback), Test-Probe / Test-DriverLoopback /
  Test-ServerBridge (all return @{Passed;Reason} hashtables).
- scripts/e2e/test-<modbus|abcip|ablegacy|s7|focas|twincat>.ps1: per-
  driver three-stage script (probe → driver-loopback → server-bridge).
  AB Legacy / FOCAS / TwinCAT are gated behind *_TRUST_WIRE env vars
  since they need real hardware (#222) or a licensed runtime (#221).
- scripts/e2e/test-phase7-virtualtags.ps1: writes a Modbus HR, reads
  the server-side VirtualTag (VT = input * 2) back via OPC UA, triggers
  + clears a scripted alarm. Exercises the Phase 7 CachedTagUpstreamSource
  + ScriptedAlarmEngine path.
- scripts/e2e/test-all.ps1: reads e2e-config.json sidecar, runs each
  present driver, prints a FINAL MATRIX (PASS/FAIL/SKIP). Missing
  sections SKIP rather than fail hard.
- scripts/e2e/e2e-config.sample.json: commented sample — each dev's
  NodeIds are local-seed-specific so e2e-config.json is .gitignore-d.
- scripts/e2e/README.md: full walkthrough — prereqs, three-stage design,
  env-var gates, expected matrix, why this is separate from `dotnet test`.

Tasks #249-#251 shipped Modbus/AbCip/AbLegacy/S7/TwinCAT CLIs but left
FOCAS out. Since test-focas.ps1 needs it, the 6th CLI ships here:

- src/ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Cli: probe/read/write/subscribe
  commands, AssemblyName `otopcua-focas-cli`. WriteCommand.ParseValue
  handles the full FocasDataType enum (Bit/Byte/Int16/Int32/Float32/
  Float64/String — no UInt variants; the FOCAS protocol exposes signed
  PMC + Fanuc-Float only). Default DataType is Int16 to match the PMC
  register convention.

Full-solution build clean (0 errors). FOCAS CLI wired into
ZB.MOM.WW.OtOpcUa.slnx. No .Tests project for the FOCAS CLI yet —
symmetric with how ProbeCommand has no unit-testable pure logic in the
other 5 CLIs either; WriteCommand.ParseValue parity will land in a
follow-up to keep this PR scoped.

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

src/ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Cli/Commands/WriteCommand.cs

@@ -0,0 +1,77 @@
+using System.Globalization;
+using CliFx.Attributes;
+using CliFx.Infrastructure;
+using ZB.MOM.WW.OtOpcUa.Core.Abstractions;
+using ZB.MOM.WW.OtOpcUa.Driver.Cli.Common;
+
+namespace ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Cli.Commands;
+
+/// <summary>
+///     Write one value to a FOCAS address. PMC G/R writes are real — be careful
+///     which file you hit on a running machine. Parameter writes may require the
+///     CNC to be in MDI mode + the parameter-write switch enabled.
+/// </summary>
+[Command("write", Description = "Write a single FOCAS address.")]
+public sealed class WriteCommand : FocasCommandBase
+{
+    [CommandOption("address", 'a', Description = "FOCAS address — same format as `read`.", IsRequired = true)]
+    public string Address { get; init; } = default!;
+
+    [CommandOption("type", 't', Description =
+        "Bit / Byte / Int16 / Int32 / Float32 / Float64 / String (default Int16).")]
+    public FocasDataType DataType { get; init; } = FocasDataType.Int16;
+
+    [CommandOption("value", 'v', Description =
+        "Value to write. Parsed per --type (booleans accept true/false/1/0).",
+        IsRequired = true)]
+    public string Value { get; init; } = default!;
+
+    public override async ValueTask ExecuteAsync(IConsole console)
+    {
+        ConfigureLogging();
+        var ct = console.RegisterCancellationHandler();
+
+        var tagName = ReadCommand.SynthesiseTagName(Address, DataType);
+        var tag = new FocasTagDefinition(
+            Name: tagName,
+            DeviceHostAddress: HostAddress,
+            Address: Address,
+            DataType: DataType,
+            Writable: true);
+        var options = BuildOptions([tag]);
+
+        var parsed = ParseValue(Value, DataType);
+
+        await using var driver = new FocasDriver(options, DriverInstanceId);
+        try
+        {
+            await driver.InitializeAsync("{}", ct);
+            var results = await driver.WriteAsync([new WriteRequest(tagName, parsed)], ct);
+            await console.Output.WriteLineAsync(SnapshotFormatter.FormatWrite(Address, results[0]));
+        }
+        finally
+        {
+            await driver.ShutdownAsync(CancellationToken.None);
+        }
+    }
+
+    internal static object ParseValue(string raw, FocasDataType type) => type switch
+    {
+        FocasDataType.Bit => ParseBool(raw),
+        FocasDataType.Byte => sbyte.Parse(raw, CultureInfo.InvariantCulture),
+        FocasDataType.Int16 => short.Parse(raw, CultureInfo.InvariantCulture),
+        FocasDataType.Int32 => int.Parse(raw, CultureInfo.InvariantCulture),
+        FocasDataType.Float32 => float.Parse(raw, CultureInfo.InvariantCulture),
+        FocasDataType.Float64 => double.Parse(raw, CultureInfo.InvariantCulture),
+        FocasDataType.String => raw,
+        _ => throw new CliFx.Exceptions.CommandException($"Unsupported DataType '{type}' for write."),
+    };
+
+    private static bool ParseBool(string raw) => raw.Trim().ToLowerInvariant() switch
+    {
+        "1" or "true" or "on" or "yes" => true,
+        "0" or "false" or "off" or "no" => false,
+        _ => throw new CliFx.Exceptions.CommandException(
+            $"Boolean value '{raw}' is not recognised. Use true/false, 1/0, on/off, or yes/no."),
+    };
+}