sx-loops-up.sh spawns a tmux session 'sx-loops' with 7 windows (lua,
prolog, forth, erlang, haskell, js, hs). Each window runs 'claude'
and then /loop against its briefing at plans/agent-briefings/<x>-loop.md.
Optional arg is the interval (e.g. 15m); omit for model-self-paced.
Each loop does ONE iteration per fire: pick the first unchecked [ ] item,
implement, test, commit, tick, log — then stop. Commits push to
origin/loops/<lang> (safe; not main).
sx-loops-down.sh sends /exit to each window and kills the session.
Attach with: tmux a -t sx-loops
