Both File and State are included. As for a full database platform we have left that out of the core stack. There are a ton of great solutions in that space for you to use that you can use in conjunction with your Project Firefly stack.
At this time we support Javascript as our core language. There are a number of higher level languages that transpile to nodejs compatable Javascript that you can use as well like TypeScript for example.
In addition to the response @dr_venture added, I also want to redirect you to https://www.youtube.com/watch?v=LbAVytUm94g&t=1s. This is a video overview of the technology stack of Firefly, with other videos in the same playlist diving into different aspects of Firefly. Hopefully, this clarifies your questions!