Basic vault prototype using OP_CAT

The discussion revolves around an implementation detail related to signature messages in a programming context, specifically focusing on how the index of the input is covered within these messages. It is highlighted that the approach taken involves referencing the index of the input within the signature message, a method detailed within the full specification found in the Bitcoin Improvement Proposal 341 (full spec in bip341). A proposal is made suggesting that by enforcing the covenant input to be at a specific index (index 0 as per the example given), potential issues could be addressed effectively. This enforcement strategy implies that the current input index being set to 0 could serve as a solution to the problem at hand.