[popover] Fix nested `openOnHover`

[atomiks]

Fixes #1932

Possible questions:

• Should the nested popover disable the useHover of the parent hovered popover like Menu does? This means it requires an outside press to dismiss rather than a hover out.
• FloatingTree can't generalize between different floating components (e.g. Popover openOnHover -> Menu openOnHover will close the Popover unexpectedly). It is possible that dot point 1 would solve this if we detected it landed in a data-floating-ui-portal (but maybe not all cases where we land in a new popup should prevent closing the parent).

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[michaldudak]

FloatingTree can't generalize between different floating components (e.g. Popover openOnHover -> Menu openOnHover will close the Popover unexpectedly). It is possible that dot point 1 would solve this if we detected it landed in a data-floating-ui-portal (but maybe not all cases where we land in a new popup should prevent closing the parent).

We can introduce a "container" context across the library, similarly to how menu parent context works. Components that can have other components nested (like dialogs, toolbars, popovers, etc.) could set up a context the will make children aware if they are placed inside. Such context could expose methods such as close so that children can control parent's behavior to a degree.