Although I gave up on it, I had a similar idea. I built "VimTools", which allowed you to navigate between different sources on a webpage (via dev tools) and edit them, vim-style. I didn't get beyond the navigation part, though.

If you can implement some Vim-style navigation and key-bindings into this, that would be awesome!

It does! I'm an avid vim user so I made sure it had ctrl-p, ctrl-w (for window switching), (slash space for search), a nerd tree equivalent file tree explorer. I build all features to be vim compliant first. Just toggle enable vim mode in the settings.