* refactor: improve menubar keyboard accessibility
* fix: create a temporary widget for tray icon context menu
* fix: focus menu bar with Alt when autohide is off
* fix: make menu bar focus work more like the native menus
* fix: only focus menu bar if it's not already focused
* fix: track accelerator registration to avoid duplicates
* docs: add docs for & notation in app menu item names
* fix: only try to activate accelerator if it's registered
* fix: add friend to monitor window focus change
* style: add <memory> include
