review(Driver.AbCip): thread ElementCount/IsArray through factory tag DTOs

Cross-module fix from the review sweep. -018 (Medium): AbCipTagDto/AbCipMemberDto dropped
elementCount/isArray, so driver-config-authored array tags read as a single scalar. Added the
two optional JSON fields (additive; missing -> scalar as before) threaded into the tag def +
TDD.

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbCip/AbCipDriverFactoryExtensions.cs

@@ -104,9 +104,13 @@ public static class AbCipDriverFactoryExtensions
                     DataType: ParseEnum<AbCipDataType>(m.DataType, t.Name, driverInstanceId,
                         $"Members[{m.Name}].DataType"),
                     Writable: m.Writable ?? true,
-                    WriteIdempotent: m.WriteIdempotent ?? false))]
+                    WriteIdempotent: m.WriteIdempotent ?? false,
+                    ElementCount: m.ElementCount is > 0 ? m.ElementCount.Value : 1,
+                    IsArray: m.IsArray))]
                 : null,
-            SafetyTag: t.SafetyTag ?? false);
+            SafetyTag: t.SafetyTag ?? false,
+            ElementCount: t.ElementCount is > 0 ? t.ElementCount.Value : 1,
+            IsArray: t.IsArray);
 
     private static T ParseEnum<T>(string? raw, string? tagName, string driverInstanceId, string field,
         T? fallback = null) where T : struct, Enum
@@ -243,6 +247,20 @@ public static class AbCipDriverFactoryExtensions
         /// Gets or sets whether this is a safety tag.
         /// </summary>
         public bool? SafetyTag { get; init; }
+
+        /// <summary>
+        /// Gets or sets the explicit 1-D array signal — <c>true</c> ⟺ the tag is an array (even a
+        /// 1-element one). Mirrors <c>AbCipTagDefinition.IsArray</c>; optional (absent ⇒ scalar).
+        /// </summary>
+        [JsonPropertyName("isArray")]
+        public bool IsArray { get; init; }
+
+        /// <summary>
+        /// Gets or sets the number of elements for a 1-D array tag; <c>1</c> (or absent) for a scalar.
+        /// Mirrors <c>AbCipTagDefinition.ElementCount</c>; only positive values are honoured.
+        /// </summary>
+        [JsonPropertyName("elementCount")]
+        public int? ElementCount { get; init; }
     }
 
     internal sealed class AbCipMemberDto
@@ -266,6 +284,20 @@ public static class AbCipDriverFactoryExtensions
         /// Gets or sets whether write is idempotent.
         /// </summary>
         public bool? WriteIdempotent { get; init; }
+
+        /// <summary>
+        /// Gets or sets the explicit 1-D array signal for the member — <c>true</c> ⟺ the member is
+        /// an array (even a 1-element one). Mirrors <c>AbCipStructureMember.IsArray</c>; optional.
+        /// </summary>
+        [JsonPropertyName("isArray")]
+        public bool IsArray { get; init; }
+
+        /// <summary>
+        /// Gets or sets the number of elements for a 1-D array member; <c>1</c> (or absent) for a
+        /// scalar. Mirrors <c>AbCipStructureMember.ElementCount</c>; only positive values are honoured.
+        /// </summary>
+        [JsonPropertyName("elementCount")]
+        public int? ElementCount { get; init; }
     }
 
     internal sealed class AbCipProbeDto