Updated BIP for OP_CAT

Additionally, there has been an update to the reference implementation. These modifications aim to enhance the proposal's clarity and effectiveness. The revised proposal is accessible through a pull request in the bitcoin/bips repository, available at https://github.com/bitcoin/bips/pull/1525. Furthermore, it is also documented as BINANA BIN-2024-0001, with its details hosted on the Bitcoin Inquisition's GitHub page at https://github.com/bitcoin-inquisition/binana/blob/master/2024/BIN-2024-0001.md. These updates play a crucial role in ensuring the proposal's alignment with current technological standards and compatibility requirements.