Quality Playbook harness

Orchestrate Quality Playbook (or any) runs across multiple repos from one agent session. Drives a disk-backed state machine one idempotent tick at a time — each tick the tick script reads workers' heartbeats, advances the state machine, and lists which workers to dispatch; the orchestrator launches them, prints the script's status table, and schedules the next tick (via ScheduleWakeup at cadence rung 1, or the foreground ticker at lower rungs). Dispatch is in-session subagents (rung 1) or detached shell workers. Runs until every job is terminal or a STOP file appears. Use when asked to run QPB against several repos at once, run a benchmark plan, or orchestrate multi-repo …