Show healthy/running/desired allocs in Job summary

### What is the problem?

The current summary data in Jobs view is not very intuitive. Currently it shows, how many groups are running out of total groups in a Job. But people are really interested on whether the desired allocs are running and healthy within a job. Something similar to the below one. This is Job overview from Nomad UI dashboard.


### How to solve?

We can show below detail in Summary.

` / / `

### Example


The allocs should be the sum of allocs from each group. (Mostly each job will have one group. I still can’t find a good use case, where we run multiple groups in a Job)

I can give a PR on this change 😎 . Let me know if this improvement make sense.

Start in the Jobs view where the current group-count summary is assembled, and trace how allocation data is collected for each job group. Update the summary to show healthy allocs / running allocs / desired allocs using totals across groups, then verify the display with jobs containing one or more groups.

Written by the indexing model from the issue text.