GET ONLY the 'Authentication' field of TitlePublicConfigurationModel. Authentication — which third-party sign-in methods the title offers and the public OAuth client IDs each platform build needs (currently Google: Web / Android / iOS / Desktop client IDs). Contains NO secrets: OAuth client IDs are public by protocol design, and none of the sign-in flows uses a client secret. Device / e-mail / Telegram / SSO logins need no configuration and are absent from this section. The ID-token audience differs per platform (web and Android tokens carry the Web client ID, iOS tokens the iOS client ID), so several IDs are filled at once and the server accepts any of them.