chore: import upstream snapshot with attribution

dotnet/tests/Foundry.Hosting.IntegrationTests/CustomStorageHostedAgentTests.cs

@@ -0,0 +1,49 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Threading.Tasks;
+using Foundry.Hosting.IntegrationTests.Fixtures;
+
+namespace Foundry.Hosting.IntegrationTests;
+
+/// <summary>
+/// Tests for a hosted agent whose container wires an in memory custom storage provider
+/// in place of the platform default. Verifies the model still works and that multi turn
+/// behavior reads from the custom store.
+/// </summary>
+[Trait("Category", "FoundryHostedAgents")]
+public sealed class CustomStorageHostedAgentTests(CustomStorageHostedAgentFixture fixture)
+    : IClassFixture<CustomStorageHostedAgentFixture>
+{
+    private readonly CustomStorageHostedAgentFixture _fixture = fixture;
+
+    [Fact(Skip = "Pending TestContainer build and end to end smoke (step 5).")]
+    public async Task RoundTrip_WorksWithCustomStorageAsync()
+    {
+        // Arrange
+        var agent = this._fixture.Agent;
+
+        // Act
+        var response = await agent.RunAsync("Reply with the word 'stored'.");
+
+        // Assert
+        Assert.False(string.IsNullOrWhiteSpace(response.Text));
+    }
+
+    [Fact(Skip = "Pending TestContainer build and end to end smoke (step 5).")]
+    public async Task MultiTurn_PreviousResponseId_ReadsFromCustomStoreAsync()
+    {
+        // Arrange
+        var agent = this._fixture.Agent;
+        var session = await agent.CreateSessionAsync();
+
+        // Act
+        var first = await agent.RunAsync("My favorite city is Lisbon. Acknowledge briefly.", session);
+        Assert.False(string.IsNullOrWhiteSpace(first.Text));
+
+        var second = await agent.RunAsync("What city did I just tell you?", session);
+
+        // Assert
+        Assert.Contains("Lisbon", second.Text, StringComparison.OrdinalIgnoreCase);
+    }
+}