readability-isolate-declaration : one declaration per line, which is KF coding style
readability-braces-around-statements: always use braces around statements, again KF coding style
I don't think this needs to be a git hook, because such issues are usually easy to spot in code review, basically it would be a one-time run (and adding the commits to .git-blame-ignore-revs so as to keep git blame path clear).
run-clang-tidy -checks='-*,readability-braces-around-statements,readability-isolate-declaration' -jN -fix