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Runtime/Model/SaveEnvelope.cs

@@ -0,0 +1,16 @@
+using System;
+using Newtonsoft.Json.Linq;
+
+namespace Jovian.SaveSystem {
+    /// <summary>
+    /// On-disk wrapper that pairs minimal metadata with the game data payload.
+    /// Payload is stored as JToken so it remains readable JSON when using JsonSaveSerializer.
+    /// </summary>
+    [Serializable]
+    public sealed class SaveEnvelope {
+        public int version;
+        public long timestampUtc;
+        public SaveSlotType slotType;
+        public JToken payload;
+    }
+}