Added nodes related to the list and array operations

Examples/Nodify.Calculator/Execution/Resolvers/NodeValueResolvers.cs

@@ -205,4 +205,88 @@ namespace Nodify.Calculator.Execution.Resolvers
             return null;
         }
     }
+
+    // ─────────────────────────────────────────────────────────────────────────────
+    // LIST GET: pick an element by index from a JSON array (non-flow value node).
+    // ─────────────────────────────────────────────────────────────────────────────
+    internal sealed class ListGetValueResolver : INodeValueResolver
+    {
+        public bool CanResolve(OperationViewModel node, ConnectorViewModel c)
+            => node is SystemOperationViewModel sys && sys.SystemOperationType == SystemOperations.LIST_GET;
+
+        public string Resolve(OperationViewModel node, ConnectorViewModel outputConnector, IValueResolutionContext ctx)
+        {
+            var listInput = node.Input.FirstOrDefault(i => i.Shape == ConnectorShape.Grid);
+            var indexInput = node.Input.FirstOrDefault(i => (i.Title ?? "").StartsWith("Index", StringComparison.OrdinalIgnoreCase));
+            if (listInput == null) return null;
+
+            var json = ctx.Read(listInput);
+            var indexStr = indexInput != null ? ctx.Read(indexInput) : "0";
+            int index = int.TryParse(indexStr, out var i) ? i : 0;
+
+            try
+            {
+                var arr = JArray.Parse(json ?? "[]");
+                if (index >= 0 && index < arr.Count)
+                {
+                    var item = arr[index];
+                    return item.Type == JTokenType.String ? item.ToString() : item.ToString(Formatting.None);
+                }
+            }
+            catch { }
+            return null;
+        }
+    }
+
+    // ─────────────────────────────────────────────────────────────────────────────
+    // LIST COUNT: returns the length of a JSON array as a string integer.
+    // ─────────────────────────────────────────────────────────────────────────────
+    internal sealed class ListCountValueResolver : INodeValueResolver
+    {
+        public bool CanResolve(OperationViewModel node, ConnectorViewModel c)
+            => node is SystemOperationViewModel sys && sys.SystemOperationType == SystemOperations.LIST_COUNT;
+
+        public string Resolve(OperationViewModel node, ConnectorViewModel outputConnector, IValueResolutionContext ctx)
+        {
+            var listInput = node.Input.FirstOrDefault(i => i.Shape == ConnectorShape.Grid);
+            if (listInput == null) return "0";
+
+            var json = ctx.Read(listInput);
+            try
+            {
+                var arr = JArray.Parse(json ?? "[]");
+                return arr.Count.ToString();
+            }
+            catch { return "0"; }
+        }
+    }
+
+    // ─────────────────────────────────────────────────────────────────────────────
+    // LIST CONTAINS: checks if item exists in array, returns "true"/"false".
+    // ─────────────────────────────────────────────────────────────────────────────
+    internal sealed class ListContainsValueResolver : INodeValueResolver
+    {
+        public bool CanResolve(OperationViewModel node, ConnectorViewModel c)
+            => node is SystemOperationViewModel sys && sys.SystemOperationType == SystemOperations.LIST_CONTAINS;
+
+        public string Resolve(OperationViewModel node, ConnectorViewModel outputConnector, IValueResolutionContext ctx)
+        {
+            var listInput = node.Input.FirstOrDefault(i => i.Shape == ConnectorShape.Grid);
+            var itemInput = node.Input.FirstOrDefault(i => i.IsCopyConnector);
+            if (listInput == null) return "false";
+
+            var json = ctx.Read(listInput);
+            var itemJson = itemInput != null ? ctx.Read(itemInput) : null;
+
+            try
+            {
+                var arr = JArray.Parse(json ?? "[]");
+                if (string.IsNullOrEmpty(itemJson)) return "false";
+                var searchToken = JToken.Parse(itemJson);
+                bool found = arr.Any(t => JToken.DeepEquals(t, searchToken));
+                return found.ToString().ToLower();
+            }
+            catch { return "false"; }
+        }
+    }
 }