Optional authentication block for a PushNotificationConfig.
Wire fields: schemes (required — list of supported scheme names like "Bearer", "Basic"), credentials (optional opaque credential payload).
schemes
credentials
@type t() :: %A2aEngine.Types.PushNotificationAuthenticationInfo{ credentials: String.t() | nil, schemes: [String.t()] }
@spec from_map(map()) :: {:ok, t()} | {:error, term()}
@spec to_map(t()) :: map()