cmake: install M2-language-server script

[d-torrance]

I just installed M2 on my new MacBook and noticed that the language server script was missing!

The homebrew package uses the cmake build, and (as usual), I don't really understand cmake that well and didn't realize we needed an additional install() . I figured that just copying it to usr-dist like we do for the autotools build was sufficient. Nope!

AI Disclosure

Claude figured out what was missing and added the fix.

[mahrud]

Oh, I hadn't seen the this script. Aside from cmake conventions, I don't think this script is the right way to go because it doesn't work if M2 isn't on the path or if you have multiple M2's on different paths, e.g. if I'm running M2 from a build directory I might not want the M2-language-server from brew to be used.

I would suggest one two options:

1. move this script to the Macaulay2/bin directory and adjust it like the M2 script to run the correct M2-binary or just call ./M2 in the same directory, then move the install call to bin/CMakeFiles.txt and remove the COPY call.
2. better yet, add this invocation as an argument to M2, e.g. startup.m2 should parse --LSP and just run this, with no extra files involved.

[d-torrance]

Ooh, yeah, I like option 1. I'm hesitant about option 2. In particular, I foresee adding command-line options to M2-language-server soon and I'd rather not conflate them with M2's command-line options.

[mahrud]

You could have a phase 0 check that if --LSP is present, option processing should stop and pass on to your script instead, similar to --silent which must be used like M2 --script blah.m2.