Unit action buttons could lock up the UI at scale

[Jeff Pihach]

ATM the env.resolve() method only takes a unit name which means we need to loop over the checked units when the user clicks retry/resolve/replace.

This method should be upgraded to take a list and then batch them out to avoid the UI lockup.

Another alternative is that this list gets sent to the server for action.

[Gary Poster (gary)]

While this may be important down the road, I'm hoping we can postpone for just a bit, at least. OTOH, if someone has some time to coordinate with Juju Core and get the API there, that would be great.