feat: support hooks

[sigoden]

Hooks

• _argc_before: call before runining any operation
• _argc_after: call after running the command

Example

_argc_before() {
  echo before
}

_argc_after() {
  echo after
}

main() {
  echo main
}

eval "$(argc --argc-eval "$0" "$@")"

$ prog
before
main
after