OpenAPI client (#2)

This PR contains the work done to add the `Open API` dependencies into the library, plus to configure a dynamically generated client based on the latest [App Store Connect OAS document](https://developer.apple.com/sample-code/app-store-connect/app-store-connect-openapi-specification.zip), downloaded from the [App Store Connect documentation](https://developer.apple.com/documentation/appstoreconnectapi/) website.

Reviewed-on: #2
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

Sources/ASConnectService/openapi-generator-config.yaml

@@ -0,0 +1,17 @@
+# ===----------------------------------------------------------------------===
+#
+# This source file is part of the ASConnectService open source project
+#
+# Copyright (c) 2025 Röck+Cöde VoF. and the ASConnectService project authors
+# Licensed under the EUPL 1.2 or later.
+#
+# See LICENSE for license information
+# See CONTRIBUTORS for the list of ASConnectService project authors
+#
+# ===----------------------------------------------------------------------===
+                    
+generate:
+    - types
+    - client
+namingStrategy: defensive
+accessModifier: public