Proposed BIP for OP_CAT

A programmer named aj is sharing a set of 3 patches that can be used to make something called "inquisition" available for experimentation on regtest. The patches can be found at this link: https://github.com/ajtowns/bitcoin/commits/202310-inq25-cat. However, aj mentions that the tests need to be updated and added. To get a better understanding, it is suggested to compare these patches with similar commits from the APO/CTV PRs which can be found at these links: https://github.com/bitcoin-inquisition/bitcoin/pull/33 and https://github.com/bitcoin-inquisition/bitcoin/pull/34.

Aj also suggests that it may be worth adding support for CSFS (Cryptographic Sorting File System) as well, if experimenting with that is desired. This would involve incorporating CSFS into the script-verify flags and deployments, instead of keeping them separate.

Aj signs off by saying "harmful cat, you say?"