[Feature request] Add any entry as Menu Item shortcut

We all know that it can be hard to browse through Retroarch menus with the huge amount options it has. Sometimes I don't even remember where I saw this or that entry.

I suggest to add an option, that could be located in Settings > User Interface > Menu Item visibility and named something like "Custom Items". When entering that option, you'd have an "Add" entry at the top, and you could then browse RA to choose which entry to add to home menu (inside red square of the following screenshot, ideally below "Explore" or the last system Item anyway)

With such a feature, we'll be able to add things from "Input", to "Start Directory" of Load content menu or even "Core Downloader". Of course not the toggleable entries, it'd make no sense in the main menu.

I'm pretty sure this feature would please everybody, Retroarch would be so much pleaseant to use.

Start with Settings > User Interface > Menu Item visibility and the Ozone menu structure shown in the issue. Define how users select non-toggleable entries, where custom shortcuts appear on the home menu, and how adding an entry is confirmed; done means entries such as Input, Start Directory, or Core Downloader can be added and accessed there.