[FIP - 450] Add Gearbox Institutional RWA Market to sfrxUSD Strategies

Summary

Authors: Frax Core Team --- ## Summary This proposal adds the Gearbox Institutional RWA lending market to the sfrxUSD AMO whitelist with a cap of $5,000,000. The market is an frxUSD-denominated lending pool collateralized entirely by regulated tokenized assets from BNY and VanEck (via Securitize) and Fasanara (via Midas). Every borrower is KYCed, all collateral is transfer-restricted at the token level besides mF-ONE, and idle liquidity sits in frxUSD earning T-Bill yield. --- ##...