Improve Update available and Check for updates

Is your feature request related to a problem? Please describe. I had Insomnia open, and heard elsewhere that there was a "new version". I went and searched the menus for an updates item and didn't find one. I went to the about dialog and saw that I had an old version, but didn't find any way to update. Describe the solution you'd like • Users should be able to visually see there's an update available, w/o staring at their screens 24x7 (i.e. growl notifications are not the way to tell users about updates) • Users should be able to check for updates by either using help> or app> and either seeing a menu item for "check for updates" or seeing a button in the about dialog Describe alternatives you've considered The fact that it's possible through preferences is true, but it is not the expected results of users today. Additional context <details><summary>Pictures of various update flows</summ…