Task #250 — AB CIP + AB Legacy test-client CLIs

Second + third of the four driver test clients. Both follow the same shape as
otopcua-modbus-cli (#249) and consume Driver.Cli.Common for DriverCommandBase +
SnapshotFormatter.

New projects:
  - src/ZB.MOM.WW.OtOpcUa.Driver.AbCip.Cli/ — otopcua-abcip-cli.
    AbCipCommandBase carries gateway (ab://host[:port]/cip-path) + family
    (ControlLogix/CompactLogix/Micro800/GuardLogix) + timeout.
    Commands: probe, read, write, subscribe.
    Value parser covers every AbCipDataType atomic type (Bool, SInt..LInt,
    USInt..ULInt, Real, LReal, String, Dt); Structure writes refused as
    out-of-scope for the CLI.
  - src/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.Cli/ — otopcua-ablegacy-cli.
    AbLegacyCommandBase carries gateway + plc-type (Slc500/MicroLogix/Plc5/
    LogixPccc) + timeout.
    Commands: probe (default address N7:0), read, write, subscribe.
    Value parser covers Bit, Int, Long, Float, AnalogInt, String, and the
    three sub-element types (TimerElement / CounterElement / ControlElement
    all land on int32 at the wire).

Tests (35 new, 73 cumulative across the driver CLI family):
  - AB CIP: 17 tests — ParseValue happy-paths for every Logix atomic type,
    failure cases (non-numeric / bool garbage), tag-name synthesis.
  - AB Legacy: 18 tests — ParseValue coverage (Bit / Int / AnalogInt / Long /
    Float / String / sub-elements), PCCC address round-trip in tag names
    including bit-within-word + sub-element syntax.

Docs:
  - docs/Driver.AbCip.Cli.md — family ↔ CIP-path cheat sheet + examples per
    command + typical workflows.
  - docs/Driver.AbLegacy.Cli.md — PCCC address primer (file letters → CLI
    --type) + known ab_server upstream gap cross-ref to #224 close-out.

Wiring:
  - ZB.MOM.WW.OtOpcUa.slnx grew 4 entries (2 src + 2 tests).

Full-solution build clean. `otopcua-abcip-cli --help` + `otopcua-ablegacy-cli
--help` verified end-to-end.

Next up (#251): S7 + TwinCAT CLIs, same pattern.

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

tests/ZB.MOM.WW.OtOpcUa.Driver.AbCip.Cli.Tests/WriteCommandParseValueTests.cs

@@ -0,0 +1,99 @@
+using Shouldly;
+using Xunit;
+using ZB.MOM.WW.OtOpcUa.Driver.AbCip.Cli.Commands;
+
+namespace ZB.MOM.WW.OtOpcUa.Driver.AbCip.Cli.Tests;
+
+/// <summary>
+///     Covers <see cref="WriteCommand.ParseValue"/>. Every Logix atomic type has at least
+///     one happy-path case plus a failure case for unparseable input.
+/// </summary>
+[Trait("Category", "Unit")]
+public sealed class WriteCommandParseValueTests
+{
+    [Theory]
+    [InlineData("true", true)]
+    [InlineData("0", false)]
+    [InlineData("on", true)]
+    [InlineData("NO", false)]
+    public void ParseValue_Bool_accepts_common_aliases(string raw, bool expected)
+    {
+        WriteCommand.ParseValue(raw, AbCipDataType.Bool).ShouldBe(expected);
+    }
+
+    [Fact]
+    public void ParseValue_Bool_rejects_garbage()
+    {
+        Should.Throw<CliFx.Exceptions.CommandException>(
+            () => WriteCommand.ParseValue("maybe", AbCipDataType.Bool));
+    }
+
+    [Fact]
+    public void ParseValue_SInt_widens_to_sbyte()
+    {
+        WriteCommand.ParseValue("-128", AbCipDataType.SInt).ShouldBe((sbyte)-128);
+        WriteCommand.ParseValue("127", AbCipDataType.SInt).ShouldBe((sbyte)127);
+    }
+
+    [Fact]
+    public void ParseValue_Int_signed_16bit()
+    {
+        WriteCommand.ParseValue("-32768", AbCipDataType.Int).ShouldBe((short)-32768);
+    }
+
+    [Fact]
+    public void ParseValue_DInt_and_Dt_both_land_on_int()
+    {
+        WriteCommand.ParseValue("42", AbCipDataType.DInt).ShouldBeOfType<int>();
+        WriteCommand.ParseValue("1234567", AbCipDataType.Dt).ShouldBeOfType<int>();
+    }
+
+    [Fact]
+    public void ParseValue_LInt_64bit()
+    {
+        WriteCommand.ParseValue("9223372036854775807", AbCipDataType.LInt).ShouldBe(long.MaxValue);
+    }
+
+    [Fact]
+    public void ParseValue_unsigned_range_respects_bounds()
+    {
+        WriteCommand.ParseValue("255", AbCipDataType.USInt).ShouldBeOfType<byte>();
+        WriteCommand.ParseValue("65535", AbCipDataType.UInt).ShouldBeOfType<ushort>();
+        WriteCommand.ParseValue("4294967295", AbCipDataType.UDInt).ShouldBeOfType<uint>();
+    }
+
+    [Fact]
+    public void ParseValue_Real_invariant_culture_decimal()
+    {
+        WriteCommand.ParseValue("3.14", AbCipDataType.Real).ShouldBe(3.14f);
+    }
+
+    [Fact]
+    public void ParseValue_LReal_handles_double_precision()
+    {
+        WriteCommand.ParseValue("2.718281828", AbCipDataType.LReal).ShouldBeOfType<double>();
+    }
+
+    [Fact]
+    public void ParseValue_String_passthrough()
+    {
+        WriteCommand.ParseValue("hello logix", AbCipDataType.String).ShouldBe("hello logix");
+    }
+
+    [Fact]
+    public void ParseValue_non_numeric_for_numeric_types_throws()
+    {
+        Should.Throw<FormatException>(
+            () => WriteCommand.ParseValue("xyz", AbCipDataType.DInt));
+    }
+
+    [Theory]
+    [InlineData("Motor01_Speed", AbCipDataType.Real, "Motor01_Speed:Real")]
+    [InlineData("Program:Main.Counter", AbCipDataType.DInt, "Program:Main.Counter:DInt")]
+    [InlineData("Recipe[3]", AbCipDataType.Int, "Recipe[3]:Int")]
+    public void SynthesiseTagName_preserves_path_verbatim(
+        string path, AbCipDataType type, string expected)
+    {
+        ReadCommand.SynthesiseTagName(path, type).ShouldBe(expected);
+    }
+}