Proposed BIP for OP_CAT

The email discusses the support for OP_CAT and the implementation of reasonable resource-consumption limiters. The sender suggests that implementing it as a UASF (User Activated Soft Fork) would help build confidence in this method. Additionally, the sender expresses support for moving forward with other opcodes once they are deemed safe and maintainable. These opcodes could be used for introspection, transaction unpinning, or vaults.