Maity: Board

Review PR #150 (runner R7a agent_user layout)

tsk-7j7gfj4wqyv3 cancelled chore

Independent review of https://github.com/oliver-zehentleitner/maity/pull/150 (agent C, stacked on #147): agent commands via sudo -n -u <agent_user> with a minimal env; agent files under ~<agent_user>/.maity-runner; runner state/credential stay the runner's. Check env passed across sudo, the documented sudoers line breadth, file ownership/modes the runner creates in the agent home and whether the runner follows paths the agent user controls (symlinks), tmux socket ownership/attach rights, signals across users, safe.directory effect on gc. Deliver review_result to oz-agent-a.