How to use the Confluence-space-ia API to configure a space sidebar?

I’ve been working on a custom plugin, which allows non space-admins to configure the sidebar of a space - without granting them all the other privileges of a space admin.
I tried recording the network requests sent when making changes to the sidebar, which gave me the following address:
This REST interface seems to be related to the confluence-space-ia
Now, I have no idea how to change the inner workings of said repository, or what the API exposed through this package looks like. Does anyone in here have any experience dealing with this package / modifying the sidebar ?