Map wrapped cancellation in the Amiibo live client to the cancelled error.

Tests/AmiiboService/Helpers/Transports/ThrowingTransport.swift

@@ -0,0 +1,48 @@
+// ===----------------------------------------------------------------------===
+//
+// This source file is part of the Amiibo Service open source project
+//
+// Copyright (c) 2026 Röck+Cöde VoF. and the Amiibo Service project authors
+// Licensed under Apache license v2.0
+//
+// See LICENSE for license information
+// See CONTRIBUTORS for the list of Amiibo Service project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// ===----------------------------------------------------------------------===
+
+import Foundation
+import HTTPTypes
+import OpenAPIRuntime
+
+/// A transport that throws a given error instead of sending the request, for testing purposes.
+///
+/// The error reaches the live client wrapped in a `ClientError`, as it would from a real transport.
+struct ThrowingTransport: ClientTransport {
+
+    // MARK: Properties
+
+    /// The error to throw.
+    private let error: any Error
+
+    // MARK: Initializers
+
+    /// Initializes this transport.
+    /// - Parameter error: An error to throw.
+    init(error: any Error) {
+        self.error = error
+    }
+
+    // MARK: Functions
+
+    func send(
+        _ request: HTTPRequest,
+        body: HTTPBody?,
+        baseURL: URL,
+        operationID: String
+    ) async throws -> (HTTPResponse, HTTPBody?) {
+        throw error
+    }
+
+}