Motivation for this change

I'm using org-roam-node-at-point to fetch the title of the node when building the agenda. Not all my agenda-items are roam-nodes themself and I want to have access to the title of the parent node. However depending on whether the heading tree is visible or collapsed I'm getting different result. Turns out it's just a matter of org-back-to-heading-or-point-min which needed invisible-ok argument.

Example of the file that show different results depending on visibility

:PROPERTIES:
:ID:       dfe77ff7-7e27-4fdd-ad7c-ffd6aadc87bd
:END:
#+title: org-roam
#+startup: overview

* test
** inner
:PROPERTIES:
:ID:       4ced70aa-7b8c-41f0-b43e-3554dbbeeb10
:END:
*** item
SCHEDULED: <2021-08-21 Sat>

The result is either "inner" or "org-roam" depending on visibility.