widgets: speed up initial load by loading timeline in bg
Previously on startup we would fetch the timeline as we build the app. This had two issues: * However long it took for the timeline to be fetched is how long it would take for our window to show * The app would crash if the timeline was not fetched. This commit makes Social more resilient, using a spinner for the timeline while it's fetched, then switching to the list of posts.
Showing with 46 additions and 18 deletions