I'd be considering using a Swift package (or Cocoapods pod!) and just releasing new versions as time goes on and things change.
Macros are not really an appropriate tool for generating static code – their power comes from being able to operate on syntax they're provided, and can enhance by removing large amounts of boilerplate. I think SPM, Carthage, Cocoapods, etc. are much better – and much, much lighter* – for distributing static code like this.
Adding macros to your package imports Swift Syntax, which means all downstream consumers of your package (which may just be yourself, of course!) also now need to download and build that ~38,000 line of code project which can bloat CI times by 12 minutes or so on Xcode Cloud. If you're offering a macro that operates on syntax that a user provides – checking a URL is valid at compile time, enhancing a type to handle writing boilerplate, etc. – then that's a price maybe worth paying. If it's just generating static code though, it's almost certainly not worth it when you could just distribute that static code.