Auto: abcip-1.3 — array-slice read addressing

Closes #227

src/ZB.MOM.WW.OtOpcUa.Driver.AbCip/LibplctagTagRuntime.cs

@@ -30,6 +30,11 @@ internal sealed class LibplctagTagRuntime : IAbCipTagRuntime
         // boundary. Null leaves libplctag at its default 82-byte STRING for back-compat.
         if (p.StringMaxCapacity is int cap && cap > 0)
             _tag.StringMaxCapacity = (uint)cap;
+        // PR abcip-1.3 — slice reads. Setting ElementCount tells libplctag to allocate a buffer
+        // covering N consecutive elements; the array-read planner pairs this with TagName=Tag[N]
+        // to issue one Rockwell array read for a [N..M] slice.
+        if (p.ElementCount is int n && n > 0)
+            _tag.ElementCount = n;
     }
 
     public Task InitializeAsync(CancellationToken cancellationToken) => _tag.InitializeAsync(cancellationToken);