I don’t use URLs in my notes but I believe storing http(s) links is for roam_refs. In this post I attempted to describe what they do. It was for V1 but I think it still applies to V2 – please correct me if I’m mistaken.
Re how to ignore http links for caching, org-roam-db-map-links
is called like this.
(org-roam-db-map-links
info
(list #'org-roam-db-insert-link))
Perhaps you could simply override org-roam-db-insert-link
and ignore links of type “http” or something for web – I believe the type
variable can be used to single out ID links.