That's exactly right, it's the same "level", as I liked to call it to non-programmers (for programmers, it's just another entry in the top level dictionary, so part of the dict = {}).
I don't believe it's included.
It's also outdated, big time. But it works, and I've never had complaints about it. And, considering the lack of bridges, no need (as of yet) for MVAM capabilities, but I may just do that (or rather, the ability to nest bridges, as you can nest ships regardless of MVAM, which is still a "default", in SubMenu V4+).
Btw, this is also valid in BridgeSubMenu:
"SubMenu": ["Enterprise Bridges", "TNG Era"],In case you have more special purpose Enterprise bridges.