I have recently been coding on iPad using a combination of Working Copy [1] and Termius [2].
[1]: https://workingcopyapp.com/
Working Copy is an amazing graphical Git client and integrates fully with iOS Files.
But for now SSH/Mosh via Termius feels closer to a traditional dev environment. It gives me full access to the command line, tmux, vim, etc., and mapping caps lock → esc sidesteps the lack of an iPad escape key and would be my default on a computer anyway.
I would love to have the best of both worlds: a traditional dev environment local to my iPad and integrated with native iOS APIs.