We are writing a plugin that depends on ACF. But while defining our custom fields via PHP, it occurs to me — won’t those acf_add_local_field functions run on every page load if we define them within something like the acf/init hook? Even if it won’t cause an issue (i.e. ACF will just recognize they exist already and exit gracefully), that seems inefficient.
I was thinking perhaps of doing it during the plugin activation hook. Is there a "best practice" for registering new custom fields such that the code to do so doesn’t get called over and over?