UX: make it more obvious that group is paused after pueue kill -g and tasks are scheduled as paused

[d33tah]

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

I recently needed to do pueue kill -g xargs -c. I was later surprised to see that newly added tasks aren't executed like they normally wood.

Describe the solution you'd like

After running pueue kill -g, print to the stderr that a group is paused. This is not necessarily an obvious consequence of pueue kill - note that e.g. Unix's kill doesn't also suspend the parent of the killed process, so I'm not exactly sure where how this behavior was inspired.

Also, it would be a good idea to warn the user that the group is paused if tasks are added to a paused group. Ideally, in a separate line and a different color so that it's more difficult to miss.

Describe alternatives you've considered

1. don't pause groups by default
   • breaks backward compatibility
2. add a way to override auto-pausing

Additional context

Tested under Pueue client 1.0.3, installed from cargo sometime last week.

[Nukesor]

The idea behind this was, that one often doesn't want any follow-up tasks to start, if all tasks in a whole group are killed.

Most of the time, a group is killed because something went wrong or a mistake has been made. By pausing the affected group, we prevent that any other malicious commands will be executed. It might be unintuitive, but it's also the solution that breaks less things.

[Nukesor]

#280

This implements your initial proposal for better output in both cases:

• When killing whole groups
• When adding tasks to paused groups.

The different color is a little tricky, as the message comes from the daemon, but the styling can only be done by the client.
There currently exists no mechanism for such behavior.