Draft: [applets/appmenu] MenuDelegate: rename State enum to MenuState
Draft status until the dependent merge request !1351 (merged) lands. Also gotta change target branches when that happens.
This patch set deals with the background item of the MenuDelegate.qml component, factoring it out and flattening to its limits.
Just as !1351 (merged), this does not really fix any bugs — it's just a more optimal code.