Ruling on the Base x402 USDC settlement market

Is the Base x402 USDC settlement market growing, is it concentrated or a real market, and who leads? Rules over TensorFeed's own on-chain settlement index: momentum versus the prior window of equal length, concentration by the Herfindahl index, and the leading publisher, plus the full per-publisher volume ranking. Optional window=24h|7d|30d (default 7d). Coverage is the Base settlements TensorFeed indexes, forward-only from launch. 10-minute freshness SLA, no-charge when stale.