I see, that's true, it could use some more publicity! Still, I think you could get in touch with Mozilla somehow already.
However, thinking more about it, it does make sense that they'd be separate since yours is more like a framework to implement various translation systems, as you said. I could still see some of the features you implemented being contributed to the Firefox Translations extension, for the sake of keeping it in scope, I'm not sure which kind of things they would like though ¯\_ (ツ) _/¯