Routing quality

For every (asked → landed) rewrite over the last 1 day, compares its success rate to the same landing model when asked natively. Success rate denominator excludes blocks — loop / budget / plan-cap blocks fire before the upstream call, so they reflect TokSuan's protection layers doing their job, not routing quality. Raw block counts are surfaced separately. A rewrite that drops ≥ 5pp below baseline on a sample of ≥ 20 calls (counting blocks too) is flagged below.