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>

tests/Server/ZB.MOM.WW.OtOpcUa.Server.Tests/ServerRedundancyNodeWriterTests.cs

@@ -0,0 +1,125 @@
+using System.Reflection;
+using Microsoft.Extensions.Logging.Abstractions;
+using Opc.Ua;
+using Opc.Ua.Server;
+using Shouldly;
+using Xunit;
+using ZB.MOM.WW.OtOpcUa.Server.Redundancy;
+using ConfigRedundancyMode = ZB.MOM.WW.OtOpcUa.Configuration.Enums.RedundancyMode;
+
+namespace ZB.MOM.WW.OtOpcUa.Server.Tests;
+
+/// <summary>
+///     Unit coverage for <see cref="ServerRedundancyNodeWriter"/>. Uses a <see cref="DispatchProxy"/>
+///     stand-in for <see cref="IServerInternal"/> — the writer only needs <c>ServerObject</c> +
+///     <c>DefaultSystemContext</c>, so we stub just those and let every other member return
+///     null (the writer never touches anything else).
+/// </summary>
+public sealed class ServerRedundancyNodeWriterTests
+{
+    [Fact]
+    public void ApplyServiceLevel_sets_node_value_and_dedupes_unchanged()
+    {
+        var env = BuildEnv();
+
+        env.Writer.ApplyServiceLevel(200);
+        env.ServerObject.ServiceLevel.Value.ShouldBe((byte)200);
+
+        var timestampAfterFirst = env.ServerObject.ServiceLevel.Timestamp;
+
+        // Same value — writer should early-out without touching Timestamp.
+        Thread.Sleep(5);
+        env.Writer.ApplyServiceLevel(200);
+        env.ServerObject.ServiceLevel.Timestamp.ShouldBe(timestampAfterFirst);
+
+        env.Writer.ApplyServiceLevel(150);
+        env.ServerObject.ServiceLevel.Value.ShouldBe((byte)150);
+        env.ServerObject.ServiceLevel.Timestamp.ShouldBeGreaterThan(timestampAfterFirst);
+    }
+
+    [Fact]
+    public void ApplyRedundancySupport_maps_config_enum()
+    {
+        var env = BuildEnv();
+
+        env.Writer.ApplyRedundancySupport(ConfigRedundancyMode.Warm);
+        env.ServerObject.ServerRedundancy.RedundancySupport.Value.ShouldBe(RedundancySupport.Warm);
+
+        env.Writer.ApplyRedundancySupport(ConfigRedundancyMode.Hot);
+        env.ServerObject.ServerRedundancy.RedundancySupport.Value.ShouldBe(RedundancySupport.Hot);
+
+        env.Writer.ApplyRedundancySupport(ConfigRedundancyMode.None);
+        env.ServerObject.ServerRedundancy.RedundancySupport.Value.ShouldBe(RedundancySupport.None);
+    }
+
+    [Fact]
+    public void ApplyServerUriArray_writes_when_non_transparent_state_present()
+    {
+        var env = BuildEnv(nonTransparent: true);
+
+        env.Writer.ApplyServerUriArray(["urn:self", "urn:peer"]);
+        var ntr = (NonTransparentRedundancyState)env.ServerObject.ServerRedundancy;
+        ntr.ServerUriArray.Value.ShouldBe(new[] { "urn:self", "urn:peer" });
+
+        var ts = ntr.ServerUriArray.Timestamp;
+        Thread.Sleep(5);
+        env.Writer.ApplyServerUriArray(["urn:self", "urn:peer"]); // dedupe
+        ntr.ServerUriArray.Timestamp.ShouldBe(ts);
+
+        env.Writer.ApplyServerUriArray(["urn:self", "urn:peer", "urn:peer2"]);
+        ntr.ServerUriArray.Value.Length.ShouldBe(3);
+    }
+
+    [Fact]
+    public void ApplyServerUriArray_skips_silently_on_base_redundancy_type()
+    {
+        var env = BuildEnv(nonTransparent: false);
+        Should.NotThrow(() => env.Writer.ApplyServerUriArray(["urn:self"]));
+        env.ServerObject.ServerRedundancy.ShouldBeOfType<ServerRedundancyState>();
+    }
+
+    private static Env BuildEnv(bool nonTransparent = false)
+    {
+        var serverObject = new ServerObjectState(parent: null)
+        {
+            ServiceLevel = new PropertyState<byte>(null),
+        };
+        serverObject.ServerRedundancy = nonTransparent
+            ? new NonTransparentRedundancyState(serverObject)
+            {
+                RedundancySupport = new PropertyState<RedundancySupport>(null),
+                ServerUriArray = new PropertyState<string[]>(null),
+            }
+            : new ServerRedundancyState(serverObject)
+            {
+                RedundancySupport = new PropertyState<RedundancySupport>(null),
+            };
+
+        var proxy = DispatchProxy.Create<IServerInternal, FakeServerInternalProxy>();
+        var fake = (FakeServerInternalProxy)(object)proxy;
+        fake.ServerObjectValue = serverObject;
+        fake.DefaultSystemContextValue = new ServerSystemContext(proxy);
+
+        var writer = new ServerRedundancyNodeWriter(proxy, NullLogger<ServerRedundancyNodeWriter>.Instance);
+        return new Env(proxy, serverObject, writer);
+    }
+
+    private sealed record Env(
+        IServerInternal Server,
+        ServerObjectState ServerObject,
+        ServerRedundancyNodeWriter Writer);
+
+    public class FakeServerInternalProxy : DispatchProxy
+    {
+        public ServerObjectState? ServerObjectValue;
+        public ISystemContext? DefaultSystemContextValue;
+
+        protected override object? Invoke(MethodInfo? targetMethod, object?[]? args) =>
+            targetMethod?.Name switch
+            {
+                "get_ServerObject" => ServerObjectValue,
+                "get_DefaultSystemContext" => DefaultSystemContextValue,
+                _ => null,
+            };
+    }
+}