fix(driver-ablegacy): resolve Low code-review findings (Driver.AbLegacy-005,011,013)

- Driver.AbLegacy-005: optional ILogger<AbLegacyDriver> ctor parameter,
  logged init failure / probe transitions / first non-zero libplctag
  status per device.
- Driver.AbLegacy-011: Dispose() runs the synchronous teardown directly
  instead of bridging via DisposeAsync().AsTask().GetAwaiter().GetResult()
  to remove the documented sync-over-async deadlock pattern.
- Driver.AbLegacy-013: documented the ResolveHost three-tier fallback
  chain in XML and pointed DiscoverAsync's IsArray=false comment at the
  Modbus ArrayCount pattern for the eventual multi-element follow-up.

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

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy/AbLegacyDriverFactoryExtensions.cs

@@ -1,5 +1,6 @@
 using System.Text.Json;
 using System.Text.Json.Serialization;
+using Microsoft.Extensions.Logging;
 using ZB.MOM.WW.OtOpcUa.Core.Hosting;
 using ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.PlcFamilies;
 
@@ -15,13 +16,23 @@ public static class AbLegacyDriverFactoryExtensions
 {
     public const string DriverTypeName = "AbLegacy";
 
-    public static void Register(DriverFactoryRegistry registry)
+    /// <summary>
+    ///     Register the AbLegacy factory with the driver registry. The optional
+    ///     <paramref name="loggerFactory"/> is captured at registration time and used to
+    ///     construct an <see cref="ILogger{AbLegacyDriver}"/> per driver instance — without it,
+    ///     the driver runs with the null logger (existing tests and standalone callers stay
+    ///     unchanged). Mirrors the Modbus driver registration pattern.
+    /// </summary>
+    public static void Register(DriverFactoryRegistry registry, ILoggerFactory? loggerFactory = null)
     {
         ArgumentNullException.ThrowIfNull(registry);
-        registry.Register(DriverTypeName, CreateInstance);
+        registry.Register(DriverTypeName, (id, json) => CreateInstance(id, json, loggerFactory));
     }
 
     internal static AbLegacyDriver CreateInstance(string driverInstanceId, string driverConfigJson)
+        => CreateInstance(driverInstanceId, driverConfigJson, loggerFactory: null);
+
+    internal static AbLegacyDriver CreateInstance(string driverInstanceId, string driverConfigJson, ILoggerFactory? loggerFactory)
     {
         ArgumentException.ThrowIfNullOrWhiteSpace(driverInstanceId);
         ArgumentException.ThrowIfNullOrWhiteSpace(driverConfigJson);
@@ -63,7 +74,10 @@ public static class AbLegacyDriverFactoryExtensions
             Timeout = TimeSpan.FromMilliseconds(dto.TimeoutMs ?? 2_000),
         };
 
-        return new AbLegacyDriver(options, driverInstanceId);
+        return new AbLegacyDriver(
+            options, driverInstanceId,
+            tagFactory: null,
+            logger: loggerFactory?.CreateLogger<AbLegacyDriver>());
     }
 
     private static T ParseEnum<T>(string? raw, string driverInstanceId, string field,