feat(apiv2): database changes

PluralKit.Core/Models/PKSwitch.cs

@@ -1,7 +1,7 @@
+using System;
+
 using NodaTime;
 
-
-
 namespace PluralKit.Core
 {
 
@@ -32,6 +32,7 @@ namespace PluralKit.Core
     public class PKSwitch
     {
         public SwitchId Id { get; }
+        public Guid Uuid { get; private set; }
         public SystemId System { get; set; }
         public Instant Timestamp { get; }
     }