RWA: xstocks-peg (077) + usdy-nav-basis (078)

[Flotapponnier]

Summary

• xstocks-peg: 12 Backed xStocks on Solana vs Yahoo, executable Jupiter mid (both directions, 1.1s spacing), Token-2022 ScaledUiAmount multiplier corrected via one batched price/v3 call, same tsp_* metric contract as 076 with issuer="xstocks" so cross-issuer comparisons are pure PromQL. Includes HOODx (Robinhood stock tokenized by a third party while absent from Robinhood's own chain)
• usdy-nav-basis: Ondo USDY market price (Orca whirlpool decoded from account bytes + Pyth market composite) vs the official Pyth redemption rate, signed basis in bps. Camelot Arbitrum pool excluded with evidence (drained to 232 USDY, frozen ~345bps under NAV)
• tokenized-stock-peg harness + spec gain the issuer="robinhood" label (bench is staging gated, series transition washes out in 24h)
• Both new benches staging gated. Smoke tested locally: xstocks deviations 4 to 47bps in regular hours, USDY basis -8.6bps