Datafix: Remove user from ALCS db

**### She's going on maternity leave again - delete both her users in prep for her return?**

**Describe the task**
ALC staff member went on maternity leave and upon return, she is in the ALCS db twice. That mean's people dont know which 'Kirsten' to select for assigning cards or mentions. Can we delete her old user with UUID = '6f063ed1-7773-418c-a462-7094ffffde6c' ? Will this cause any problems on cards that were assigned to her old user?

Update: we have another duplicate user to delete: 367b593b-fee9-41e5-bc66-2b6487fdf9e3

**Acceptance Criteria**
- [ ] save a back up in case we need to roll it back, we've never done this before
- [ ] delete users
- [ ] uuid = 6f063ed1-7773-418c-a462-7094ffffde6c
- [ ] uuid = 367b593b-fee9-41e5-bc66-2b6487fdf9e3

No files, tests, or entry points are named. Start by locating the database records for the two UUIDs and reviewing how assigned cards reference them; verify a restorable backup before any deletion. Done means both duplicate users are removed without breaking those references, with rollback supported by the backup.

Written by the indexing model from the issue text.