A gaming startup is launching a new mobile game with a companion leaderboard service backed by Amazon DynamoDB. Traffic patterns are completely unknown at launch and are expected to swing dramatically—from near-zero during off-peak hours to massive, unpredictable spikes when the game is featured or goes viral. The team wants to avoid throttling during sudden spikes and does not want to spend time forecasting throughput or managing capacity. Which DynamoDB configuration best meets these requirements?