Clarify login privilege usage
- Close picodata#492 (closed)
- Close picodata#493 (closed)
- Close #172 (closed)
- Target branch: main
- Changes should be cherry-picked to 24.1: yes
- Staging: https://docs.binary.picodata.io/picodata/branch-e-ivkov-login-user-story/
Edited by Yaroslav Dynnikov