chore: organize solution into module folders (Core/Server/Drivers/Client/Tooling)

Group all 69 projects into category subfolders under src/ and tests/ so the
Rider Solution Explorer mirrors the module structure. Folders: Core, Server,
Drivers (with a nested Driver CLIs subfolder), Client, Tooling.

- Move every project folder on disk with git mv (history preserved as renames).
- Recompute relative paths in 57 .csproj files: cross-category ProjectReferences,
  the lib/ HintPath+None refs in Driver.Historian.Wonderware, and the external
  mxaccessgw refs in Driver.Galaxy and its test project.
- Rebuild ZB.MOM.WW.OtOpcUa.slnx with nested solution folders.
- Re-prefix project paths in functional scripts (e2e, compliance, smoke SQL,
  integration, install).

Build green (0 errors); unit tests pass. Docs left for a separate pass.

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

src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.AbCip.Cli/Commands/ProbeCommand.cs

@@ -0,0 +1,58 @@
+using CliFx.Attributes;
+using CliFx.Infrastructure;
+using ZB.MOM.WW.OtOpcUa.Driver.Cli.Common;
+
+namespace ZB.MOM.WW.OtOpcUa.Driver.AbCip.Cli.Commands;
+
+/// <summary>
+///     Probes an AB CIP gateway: initialises the driver (connects via libplctag), reads a
+///     single tag, and prints health + the read result. Fastest way to answer "is the PLC
+///     up + reachable + speaking CIP via this path?".
+/// </summary>
+[Command("probe", Description = "Verify the AB CIP gateway is reachable and a sample tag reads.")]
+public sealed class ProbeCommand : AbCipCommandBase
+{
+    [CommandOption("tag", 't', Description =
+        "Tag path to probe. ControlLogix default is '@raw_cpu_type' (the canonical libplctag " +
+        "system tag); Micro800 takes a user-supplied global (e.g. '_SYSVA_CLOCK_HOUR').",
+        IsRequired = true)]
+    public string TagPath { get; init; } = default!;
+
+    [CommandOption("type", Description =
+        "Logix atomic type of the probe tag (default DInt).")]
+    public AbCipDataType DataType { get; init; } = AbCipDataType.DInt;
+
+    public override async ValueTask ExecuteAsync(IConsole console)
+    {
+        ConfigureLogging();
+        var ct = console.RegisterCancellationHandler();
+
+        var probeTag = new AbCipTagDefinition(
+            Name: "__probe",
+            DeviceHostAddress: Gateway,
+            TagPath: TagPath,
+            DataType: DataType,
+            Writable: false);
+        var options = BuildOptions([probeTag]);
+
+        await using var driver = new AbCipDriver(options, DriverInstanceId);
+        try
+        {
+            await driver.InitializeAsync("{}", ct);
+            var snapshot = await driver.ReadAsync(["__probe"], ct);
+            var health = driver.GetHealth();
+
+            await console.Output.WriteLineAsync($"Gateway:      {Gateway}");
+            await console.Output.WriteLineAsync($"Family:       {Family}");
+            await console.Output.WriteLineAsync($"Health:       {health.State}");
+            if (health.LastError is { } err)
+                await console.Output.WriteLineAsync($"Last error:   {err}");
+            await console.Output.WriteLineAsync();
+            await console.Output.WriteLineAsync(SnapshotFormatter.Format(TagPath, snapshot[0]));
+        }
+        finally
+        {
+            await driver.ShutdownAsync(CancellationToken.None);
+        }
+    }
+}