Hi

When uploading a "compiled" component to the ServiceNow Instance, the "source code" for it will not be uploaded. 

Knowing that, it will not be possible to "download" the source code for any component from the ServiceNow Instance (yet). So, your proposal or idea is correct, to create some repository (like on GitHub) for you to share the code. Also make sure, to make separate backups of your code, as you can not get this back from your ServiceNow Instance.

Publishing is a one-way process.

BR

Dirk