Navigation: Try filtering by show_in_nav_menus for post types and taxonomies

[gwwar]

WIP Part of WordPress/gutenberg#24814 this PR experiments with allowing post types and taxonomies to be filtered by show_in_nav_menus. This will be used to help build the navigation/menu flows.

Experiments with if we need to expose show_in_nav_menus and show_ui for the post type response.

TODO: update related unit tests

[github-actions]

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[gwwar]

Going to close this draft out for now in favor of WordPress/gutenberg#29095