Adds tag support to construction (#3386)

Content.Shared/Construction/TagConstructionGraphStep.cs

@@ -0,0 +1,25 @@
+#nullable enable
+using System.Collections.Generic;
+using Content.Shared.GameObjects.Components.Tag;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Serialization;
+
+namespace Content.Shared.Construction
+{
+    public class TagConstructionGraphStep : ArbitraryInsertConstructionGraphStep
+    {
+        private string? _tag = null;
+
+        public override void ExposeData(ObjectSerializer serializer)
+        {
+            base.ExposeData(serializer);
+
+            serializer.DataField(ref _tag, "tag", null);
+        }
+
+        public override bool EntityValid(IEntity entity)
+        {
+            return !string.IsNullOrEmpty(_tag) && entity.HasTag(_tag);
+        }
+    }
+}