`ContextMenu` -> `ContextMenuArea`
`ContextMenu` must have a `Menu` child.
`MenuItem` can no longer be put dirrectly in `MenuBar` and can no longer
have children
`Menu` is used now for sub menus
This can only be used internally by the style to implement the actual
ContextMenu
Only the declarative `MenuItem` interface is exposed.
* [autofix.ci] apply automated fixes
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Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>