backup your codes.
git clone https://github.com/NodeBB/NodeBB.git
switch to tag that you modified from. Perhaps, v0.4.3? e.g. git checkout v0.4.3
rsync your codes to the clone.
git commit, git tag my_tag, git checkout master, git merge my_tag
You may have to solve conflicts by yourself.
@pitaj Having a branch for the production version with a similar dump output is actually a great idea. You can solve the conflicts during git merge (or PRs if there would be a tea working on this) and there should be no problem.