FSE: Unified keyboard shortcuts for sidebars

[critterverse]

As keyboard shortcuts are in the process of being implemented in the Full Site Editor as a part of #21245, it might be a good time to discuss potential keyboard shortcuts for the additional sidebars that have been added.

The sidebars that can be toggled from the top toolbar, from left to right, are:

• Full Site Editor navigation
• Inserter
• List View (existing shortcut: ^⌥O)
• Settings (existing shortcut: ⇧⌘,)
• Global Styles

*Please comment below if I'm missing any existing sidebar shortcuts

I can imagine wanting to unify the open/closing behavior of all the sidebars through similar, easy-to-remember shortcuts. For example, each of the sidebars could be given some variation of the existing shortcut for toggling Settings or List View.

A different approach could be to make it easy to cycle through all the possible sidebar configurations via a shortcut similar to the one used for jumping to the next part of the editor: ^⌥N. Whereas the current shortcut cycles through the open sections of the editor, a new shortcut could cycle through each of the possible sidebar configurations, opening each sidebar one at a time (including an "all closed" state).

Would love to discuss which approach could best help improve usability in the FSE.

[critterverse]

Closing this issue as navigation in the site editor nows behaves differently.