[Chapel Merge] Doc & Highlight operator changes

Branch: refs/heads/main
Revision: 4c78dd8
Author: aconsroe-hpe
Log Message:

Merge pull request #18544 from aconsroe-hpe/proc-operator-2

Doc & Highlight operator changes

I found some more places where proc was being used instead of operator in the language spec and updated them.

I also added the operator keyword to all the highlight files. Pygments was already covered and textmate is external and it wasn't 100% clear at first glance where the right place to add it was.

Reviewed by @lydia-duncan

Docs built and inspected. Highlighters tested with their respective programs for a before & after inspection

Modified Files:
M doc/rst/language/spec/expressions.rst

M doc/rst/language/spec/ranges.rst
M highlight/emacs/chpl-mode.el
M highlight/geany/filetypes.Chapel.conf
M highlight/latex/chapel_listing.tex
M highlight/source-highlight/chpl.lang
M highlight/vim/syntax/chpl.vim

Compare: https://github.com/chapel-lang/chapel/compare/0c4e604849b8...4c78dd81eaa6