Feel free to add your ideas, enhancements and bug fixes to this project.
You can create your own account on this instance, but it has be be acknowledge by either me or the admin - which is me again :-) - to prevent spam and other DoS problems. So better write an additional email after initial registration to me
Just use the default git way to work with given projects, add a ticket to the main project or create merge requests.
I am no lawyer, but if you add code you might want to be named in some place in the documentation or code. Just add your wishes.