Feature request: count of edge responses with 400s errors and 500s errors

[vcajes]

Hello team, just sharing one idea in case it is of your interest.

Cloudflare is the front ingress to our services. However, when there are issues between cloudflare and our ingress (ie: traffic doesn't even arrives to our services), Cloudflare is the only source of truth for these errors.

So would be very nice to have the count of requests with status codes for 400s and also for 500s per zone, so we can have alerts for these cases.

I hope you find this feature useful. Thanks for the amazing work here.