Authentication Architecture Auth Method Selection Default is email/password + anonymous guest. Only add other methods when the user explicitly asks: - Nothing specified → email/password + anonymous guest - "Apple Sign In" or "Sign in with Apple" → Apple Sign In - "Google Sign In" → Google Sign In (requires GoogleSignIn package) - "social login" → Apple + Google - "guest mode" or "browse without account" → anonymous only - Methods combine: user can request email + Apple + anonymous Service Architecture is — it owns all auth state and lives in , NOT inside . ViewModels consume via init injectio…