Add utility AI (#806)

Co-authored-by: Pieter-Jan Briers <pieterjan.briers@gmail.com>
Co-authored-by: Metal Gear Sloth <metalgearsloth@gmail.com>
Co-authored-by: Pieter-Jan Briers <pieterjan.briers+git@gmail.com>

Content.Server/AI/Operators/Inventory/EquipEntityOperator.cs

@@ -0,0 +1,38 @@
+using Content.Server.GameObjects;
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Server.AI.Operators.Inventory
+{
+    public sealed class EquipEntityOperator : AiOperator
+    {
+        private readonly IEntity _owner;
+        private readonly IEntity _entity;
+        public EquipEntityOperator(IEntity owner, IEntity entity)
+        {
+            _owner = owner;
+            _entity = entity;
+        }
+
+        public override Outcome Execute(float frameTime)
+        {
+            if (!_owner.TryGetComponent(out HandsComponent handsComponent))
+            {
+                return Outcome.Failed;
+            }
+            // TODO: If in clothing then click on it
+            foreach (var hand in handsComponent.ActivePriorityEnumerable())
+            {
+                if (handsComponent.GetHand(hand)?.Owner == _entity)
+                {
+                    handsComponent.ActiveIndex = hand;
+                    return Outcome.Success;
+                }
+            }
+
+            // TODO: Get free hand count; if no hands free then fail right here
+
+            // TODO: Go through inventory
+            return Outcome.Failed;
+        }
+    }
+}