4f4b34ea89
Guards against the Akka singleton Ask hang regression: asserts all nine KPI tiles on /monitoring/health resolve to numeric values and never show the em-dash degrade placeholder (—). Covers Notification Outbox, Audit, and Site Call tile groups. Selector disambiguation: Outbox tiles are div.card, Site Call tiles are button.card — prevents strict-mode collisions on the shared "Stuck" and "Parked" labels.