Going over /custom/conf/app.ini.sample, it seems that I can use DISABLE_REGULAR_ORG_CREATION (and/or DEFAULT_ALLOW_CREATE_ORGANIZATION?) to prevent users from setting up new organizations. So that one issue that has a resolution. This only leaves the issue of controlling repositories.
https://docs.gitea.io/en-us/administration/config-cheat-sheet/ states that:
MAX_CREATION_LIMIT: -1 : Global maximum creation limit of repositories per user,-1means no limit.
This implies that disabling the creation of repositories for users is possible by setting that value to 0. This also implies (by the use of the word “Global”) that there is a local, per-user setting. Where can I configure the per-user repository limit?
Where can I find documentation about Gitea’s user interface and admin options in general? https://docs.gitea.io doesn’t seem to document this aspect of Gitea at all.