sdk: LoginWithCustomAsync + regenerated auth models

Services/AuthService.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Threading;
 using System.Threading.Tasks;
+using Newtonsoft.Json.Linq;
 using RudderSdk.Core.Models.Auth;
 
 namespace RudderSdk.Core;
@@ -41,7 +42,39 @@ public sealed class AuthService
                 DeviceId = _client.DeviceIdProvider.DeviceId,
                 Region = region,
                 Language = language,
-                Nickname = nickname!
+                Nickname = nickname
+            },
+            cancellationToken).ConfigureAwait(false);
+
+        if (response == null || string.IsNullOrEmpty(response.AccessToken) || string.IsNullOrEmpty(response.RefreshToken))
+            throw new InvalidOperationException("The server returned an incomplete session.");
+
+        _client.TokenStore.SaveTokens(response.AccessToken, response.RefreshToken);
+        NotifySignedIn();
+        return response;
+    }
+
+    /// <summary>
+    /// Signs the player in through the project's custom authorization webhook.
+    /// The returned token pair is stored in the configured token store.
+    /// </summary>
+    public async Task<LoginViaCustomResponse> LoginWithCustomAsync(
+        JToken customData,
+        string region,
+        string language,
+        string? nickname = null,
+        CancellationToken cancellationToken = default)
+    {
+        var response = await _client.SendAsync<LoginViaCustomRequest, LoginViaCustomResponse>(
+            "POST",
+            "/sdk/v1/authorization/custom",
+            new LoginViaCustomRequest
+            {
+                Key = _client.ProjectKey,
+                CustomData = customData,
+                Region = region,
+                Language = language,
+                Nickname = nickname
             },
             cancellationToken).ConfigureAwait(false);