save checkpoint

src/Platform/StellaOps.Platform.WebService/Contracts/SetupWizardModels.cs

@@ -3,6 +3,7 @@
 // Sprint: SPRINT_20260112_004_PLATFORM_setup_wizard_backend (PLATFORM-SETUP-001)
 // Task: Define setup wizard contracts and step definitions
 
+using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Text.Json.Serialization;
 
@@ -394,6 +395,12 @@ public sealed record SkipSetupStepRequest(
 public sealed record FinalizeSetupSessionRequest(
     bool Force = false);
 
+/// <summary>
+/// Request to test connectivity for a setup step.
+/// </summary>
+public sealed record TestConnectionRequest(
+    Dictionary<string, string>? ConfigValues = null);
+
 #endregion
 
 #region API Responses