Dashboard: Show failed jobs or sort by job status

[fgaz]

Is your feature request related to a problem? Please describe.

As a maintainer of many packages, I'd like to know when one of them fails to build

Describe the solution you'd like

I'd like https://hydra.nixos.org/dashboard/[email protected] to have a button to show only failed builds or to sort by build status

Describe alternatives you've considered

• https://zh.fail
• re-enable emails
• #743

Additional context