New per-Sandbox CPU, memory, and CPU pressure charts

Apps that run Sandboxes now have three additional aggregate metrics charts: per-Sandbox CPU, memory, and CPU pressure. Each chart plots usage against the requested resources, so you can see at a glance whether your Sandboxes are sized appropriately.

When all Sandboxes in an app share the same request, the chart labels it simply as "Request"; when requests vary, it shows the median.