Port Agent Runtime abstractions / inprocess runtime (#149)

dotnet/src/Microsoft.Extensions.AI.Agents.Runtime.Abstractions/ISaveState.cs

@@ -0,0 +1,33 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Text.Json;
+using System.Threading.Tasks;
+
+namespace Microsoft.Extensions.AI.Agents.Runtime;
+
+/// <summary>
+/// Defines a contract for saving and loading the state of an object.
+/// The state must be JSON serializable.
+/// </summary>
+public interface ISaveState
+{
+    /// <summary>
+    /// Saves the current state of the object.
+    /// </summary>
+    /// <returns>
+    /// A task representing the asynchronous operation, returning a dictionary
+    /// containing the saved state. The structure of the state is implementation-defined
+    /// but must be JSON serializable.
+    /// </returns>
+    ValueTask<JsonElement> SaveStateAsync();
+
+    /// <summary>
+    /// Loads a previously saved state into the object.
+    /// </summary>
+    /// <param name="state">
+    /// A dictionary representing the saved state. The structure of the state
+    /// is implementation-defined but must be JSON serializable.
+    /// </param>
+    /// <returns>A task representing the asynchronous operation.</returns>
+    ValueTask LoadStateAsync(JsonElement state);
+}