Porting lgi for Lua5.4

DISCLAIMER: it's not a true issue cause I know this library isn't being developed for Lua5.4

So, I have been trying to compile this library for Lua5.4. I am using Fedora 40 and I was trying to see if this library worked with some minor changes. First of all, after having installed lua-devel and compat-lua-devel, I changed, inside the makefile in the lgi library , the version from 5.1 to 5.4 I tried to run the makefile (with sudo in front of it) and it "installed", then, after having tried to run it, nothing worked.
I went back to the makefile (always inside lgi folder) and, I don't know why, but I had to change PREFIX from /usr/local to /usr and in LUA_LIBDIR I changed lib to lib64.
I then tried to run the makefile in the main folder again and, other than some compilation warnings, I didn't have any other problem. I then tried to run the console.lua program with lua console.lua and it gave me errors with GtkSource, so I thought it was a version problem and changed inside the lua file I was trying to run GtkSource's version from 3.0 to 4.0. I also tried to understand why it gave me problems with GtkSource, but I really don't understand much about GTK, therefore I am writing this "adventure" in order to let people start from where I failed.

Feel free to correct things I did wrong. Thanks for your attention!

Start by reproducing the reported Lua 5.4 build using the lgi Makefile and the top-level Makefile on Fedora 40, then run console.lua to confirm the GtkSource failure. The issue does not define a specific change or acceptance criteria; a useful outcome would require a documented, working Lua 5.4 port with the console example running successfully.