The hook rang the terminal bell by walking the process ancestry for a
process named `claude`, but nix wraps the binary so its `comm` is
`.claude-wrapped`.
The match never fired: the bell never rang, and the loop fell through to
a non-zero exit that surfaced as a Stop hook error on every turn.
Remove the hook, its script, and the Stop and Notification wiring.
The tmux monitor-bell config is left in place as a general nicety.
alexion
6f34c95c51