mod_auth_oauth_external: Allow different username in PLAIN vs final JID Mastodon for example having email addresses usernames in login, but a different username in the service itself. Thanks to @tcit@social.tcit.fr for the pointer to a usable validation endpoint for Mastodon, allowing this to be tested.

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summary: Store authentication events in the audit log
rockspec:
  dependencies:
  - mod_audit
...

This module stores authentication failures and authentication successes in the
audit log provided by `mod_audit`.