Re: Add 64-bit XIDs into PostgreSQL 15

Here is a new rebase @ 70a13c528b6e382a381f that includes solutions for the previously mentioned issues as well as 

a few more fixes and tweaks.

I decided to eliminate the TOAST flag for the function's parameters and instead check pg_special for it.

As a result of 15a79c73111f0c9 and a0ed19e0a9efe9, we also have to utilise the PRI* format string. At the moment, I'm 

not sure how to integrate this into the existing patch set. I simply added it on top of the existing ones. The only possibility 

appears to be to return to the previous version in which the primary patch of XIDs and the patch changing the message 

format to 64 bits were combined.