Fix update details on focus

[Edgpaez]

When doing a push or a fetch that didn't change the change_id, the pane view (that shows the jj show view in the right) was not refreshed. This meant that even though the push finished you wouldn't see the bookmark from the remote being added to the change.

This PR fixes this while relying on the fix from #188. I guess once we merge #188 I can rebase to only show the fix for this that is only this: 4fca823

TBH, I am a bit unsure of the broader impact this skip had in the app. So far in my tests it hasn't been a problem. I will be using this daily and will report back if I find any problems 👍

[dotdash]

Gah, sorry, I forgot that the "Update branch" does a freakin' merge

[dotdash]

A major problem I noticed with this is that each time I focus the lazyjj window, the scroll offset of the detail pane gets reset. That's a major annoyance for me, because I often switch between e.g. my vim window and the lazyjj window, where I'm looking at a diff. Losing the scroll offset each time makes this kind of unusable.

[peso]

I have notice the scroll-reset in a number of other situations as well. I think a separate PR for remembering scroll location would be good. Perhaps combined with a key like Home to reset the scroll manually.

[Edgpaez]

Ah yes, resetting the scroll position is something I am probably used to and as @peso mentioned, happens in other scenarios. In my workflow is a small price to pay for being sure I'm always looking at the latest/current version of the log and diff.

I think we can work something out to only render the pane if the diff changed... I'll give that a try 👍