Fixes#12564. Fixes#8951.
This introduces a new setting, `ADD_MEMBERS_BY_INVITATIONS`, which is turned off by default.
When turned on, adding a user to a team issues an invitation instead of adding them directly to the team.
A prerequisite for this work was to be able to link invitations to existing users (so far, they were only associated to an email address, since those invitations were meant to be issued to users who didn't have an account yet).
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I plan to work on the following improvements, which I propose to do in separate PRs given that this one is already a bit big:
* generate an in-app notification for the invited user
* advertise the invitation to the invited user from the org page as well (#12120)
* show the list of invited users in the list of organization members (not just on the team page)
and various other improvements to invitations (#12570, #12716).
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/12845
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Change all license headers to comply with REUSE specification.
Fix#16132
Co-authored-by: flynnnnnnnnnn <flynnnnnnnnnn@github>
Co-authored-by: John Olheiser <john.olheiser@gmail.com>
