[BIP-931] Balancer x CoWSwap Tokenswap and token purchase

Summary

Balancer x CoWSwap Tokenswap and token purchase Simple Summary This BIP proposes that Balancer DAO and CoW DAO revert the tokenswap performed under BIP-770, with COW DAO Managed Treasury purchasing the remaining COW owned by Balancer DAO at a 15day TWAP. Motivation In January 2025, Balancer DAO and CoW DAO executed a tokenswap under [BIP-770] of 200,000 BAL for...