Access Provisioning Capstone: Fix a Carelessly-Provisioned Project Environment

A new project environment was provisioned carelessly. Correct all six identity & access facts so the team can collaborate safely. Grading checks live with id/getent/stat; see /root/brief.txt for the exact names.

1. Missing group — the project group doesn't exist yet. It should.

2. Group membership — the developer user isn't a member of that project group, but needs to be (as a supplementary group).

3. Shared directory — the shared directory isn't set up for group collaboration: it should be owned by the project group, with mode 2775 (rwx for owner and group, r-x for others), and configured so that files created inside it inherit that group automatically.

4. Service account — a service account has been given an interactive login shell. A service account should not be able to log in.

5. Home ownership — the developer's home is owned by root instead of by the user who lives there. It should belong to that user and to their own primary group (owner and group both the developer).

6. Login shell — a real user who needs to log in has been left with a no-login shell. Give them a working one.