I've set `lexical-binding` to `nil` in all Emacs Lisp files to suppress
the warnings introduced in Emacs 31 requiring all elisp files to have a
`lexical-binding` comment.
This retains the default behavior of dynamic binding when no
`lexical-binding` comment is present. With it set to `t` across the
board, various things break, and fixing those is a task for another day.
There are a few major modes which are not based on prog-mode, that I
want to behave like prog-mode. Previously each did nearly all the same
setup that's done via the prog-mode hooks. Now instead let's actually
run runs the hooks for prog-mode.