Fork and rehost coc-zls under zigtools org

[Pyrolistical]

The instructions for Coc https://github.com/zigtools/zls/wiki/Installation#with-extension say to use :CocInstall coc-zls

Coc uses npm under the hood, so it finds https://www.npmjs.com/package/coc-zls, which is owned by https://github.com/xiyaowong

No offense to @xiyaowong, but if that account ever gets compromised, all users of coc-zls are compromised. If we need to trust zls anyways, then zigtools should rehost coc-zls.