Auto: ablegacy-7 — array contiguous block addressing

Closes #250

tests/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.Tests/FakeAbLegacyTag.cs

@@ -60,6 +60,25 @@ internal class FakeAbLegacyTag : IAbLegacyTagRuntime
         return Value;
     }
     public virtual void EncodeValue(AbLegacyDataType type, int? bitIndex, object? value) => Value = value;
+
+    /// <summary>
+    ///     PR 7 — array contiguous-block element decoder. Tests seed <see cref="ArrayValues"/>
+    ///     with the per-index payload; the fake then returns each element in order. Falls back
+    ///     to <see cref="Value"/> when the test only seeded a scalar (Convert.ChangeType handles
+    ///     the cast back to the requested element type in the driver's BuildArray helper).
+    /// </summary>
+    public IReadOnlyList<object?>? ArrayValues { get; set; }
+    public AbLegacyDataType? LastArrayDecodeType { get; private set; }
+    public int LastArrayDecodeMaxIndex { get; private set; } = -1;
+    public virtual object? DecodeArrayElement(AbLegacyDataType type, int elementIndex)
+    {
+        LastArrayDecodeType = type;
+        if (elementIndex > LastArrayDecodeMaxIndex) LastArrayDecodeMaxIndex = elementIndex;
+        if (ArrayValues is not null && elementIndex < ArrayValues.Count)
+            return ArrayValues[elementIndex];
+        return Value;
+    }
+
     public virtual void Dispose() => Disposed = true;
 }