User profile deletion concept

If a user deletes his profile we need a concept, how to handle related data F.e. forum entries, extensions, comments, events, accounts in related systems (forge, wiki, ...).

Steps:

1. user must be deleted from the main user storage (currently typo3.org fe_user, later LDAP / My.typo3.org)
2. we need a message queue, where we notify the systems or create a large task:

• forge - manually as admin in admin tool ( search user and delete as admin )
• my.typo3,org / typo3.org / extension.typo3.org - ( TYPO3 BE - List View - Delete User - NO LOGIN SHOULD BE POSSIBLE ANY MORE )
• wiki (uid der Änderungen) - ( Via MySQL, User is CamelUpperCase, Username must also be modified from change table )
• gerrit (commits löschen) - ( If User gets deleted, we get inconsistency, so we just rename a user + username )
• gitlab? ( search user and delete as admin )
• discuss
• decisions ( search user and delete as admin )
• slack
• mailman ( manage members to delete user, and delete plaintext text manually )
• forum.typo3.org ( as admin call "delete all content of user" script in admin area and delete user in user list )

In normal cases we just delete the fe_user and ldap user and keep the other services untouched. We will keep the deleted username in ldap as a "disabled user", so that that username never can be used again.