Fix drone hat offset (#6978)

Content.Shared/Inventory/InventoryTemplatePrototype.cs

@@ -34,6 +34,11 @@ public sealed class SlotDefinition
     [DataField("dependsOn")] public string? DependsOn { get; }
 
     [DataField("displayName", required: true)] public string DisplayName { get; } = string.Empty;
+
+    /// <summary>
+    ///     Offset for the clothing sprites.
+    /// </summary>
+    [DataField("offset")] public Vector2 Offset { get; } = Vector2.Zero;
 }
 
 public enum SlotUIContainer