An indent hook automatically adds whitespace, so it seems prudent to
add the hook to remove unwanted whitespace again. This is what we do
in most languages already.
This should cover all filetypes that already auto-insert comments,
except for rust.kak, which is left for a follow-up.
Most of these are straightforward, some explanation for special cases:
rc/filetype/zig.kak rc/filetype/cue.kak
These indent hooks used their own logic to indent after "{" only if
no comment was inserted. Replace this logic by checking if a comment
was inserted. This works because these "*-insert" hooks are run
before their respective "*-indent" hooks.
rc/filetype/php.kak
This also has some logic to insert "*" after "/*" lines. Basic
usage seems to work still. In future this should borrow from the
c-family one, which works a bit better.
