Raise Aave V3 BTC.b Supply Cap to 80

LlamaRisk recommends raising Aave V3 Core's BTC.b supply cap from 40 to 80. Utilization sits at 49.8% (19.93/40). Top suppliers hold health factors 1.12–2.06, borrowing stablecoins across USDe, GHO, USDT, USDC. New cap equals 4.0x current supply, ~24.9% post-change utilization. Borrow cap unchanged; implementation via Risk Steward process.