- Stats snapshot now computes the KPI totals AND the breakdown from the
in-window per-minute buckets (previously they used all-time accumulators, so
switching 1h/24h/7d changed only the chart, not the numbers). Buckets now
carry failovers + per-group breakdown; Prometheus keeps all-time counters.
- New DELETE /admin/api/stats clears all in-memory stats and truncates the
JSONL log; the dashboard gets a "Clear logs" button (with confirm).