Add the ViewSwitcher-grade menu model to the R8 popover platform, via
Floating UI's idioms rather than a second hand-rolled roving engine:
useListNavigation (↑/↓/Home/End roving, focusItemOnOpen so both click- and
key-opens land on the first item), useTypeahead, and FloatingFocusManager
(trap into the surface, return focus to the trigger on close). A new
<PopoverItem> self-registers for navigation and carries the right role
(menuitem / menuitemradio+aria-checked / option+aria-selected); menu/listbox
surfaces are focus-managed by default.
Wire the ChannelTags editor as the pilot: tag toggles become menuitemradio,
and the inline create-input stopPropagations non-Escape keys so arrows and
typed chars stay in the field (typeahead off for that menu).
peter
5d1854b808