I like to reuse some code of a GIT maintained project for another project. The working code is a good kickstart to the new project, despite most of it would come obsolete for the new needs. So the question is what would be the best practice for handling that?
I could
Make a new repository for the new thing and cherry pick the files from the old project. After stripping the code to match the needed basic funcitonality of the new project do the first commit to keep it's history clean from useless things. Maybe it takes some time to conform this goal. Also, there is no way to merge enhancements done in the old project.
Branch the old code and adapt it to it's new job step by step. That means the two projects will stay entangled inside one repository, that has one name, one README on GitHub etc.
Create the new project, beginning with a minimal main part, and another library project, serving as a common collection for both the old and the new project. However, with HTML and JS development, that makes many headaches as importing is complex in JS, impossible in HTML, there is the need to pull two repo's to get each of the project running etc.
What would you do? Are there any GIT tricks that would support me?