As Nintendo changed the way the tools are checked for breaking, a new method is now used to make them unbreakable. Unlike discussed in the comments, from my testing my version still appears to be unlimited, but thanks to Troa11 for pointing me in the right direction. Should work for all 1.4 versions
Updated mod to use the latest game files. Downloads are below with ending "-v130.zip".
Applied the mod to the latest game files
A simple mod to make gold tools unbreakable and worth their while.