I have this
(setq org-agenda-files (directory-files-recursively "~/Dropbox/org/journal/" "\\.org$"))
but I don't know where to place it in order to make sure that on the event of a new daily org-journal file creation in my journal directory (e.g. ~Dropbox/org/journal/2021/02/) the agenda file list will immediately be updated. At the moment I have it placed early in my init.el, which thereafter calls a big, general config.org full of package initializations and tweaks, then a private
custom-set-variables file. Does this sexp need to be part of some special trigger/hook/event code to know to update the
org-agenda-files list when a new org-journal day file appears?