Since you're class A software, an architecture description isn't required - which is normally where you'd put the discussion of interfaces. So you don't need that for 62304 compliance but you will need something. I'd probably recommend a cybersecurity write-up with that assertion, concluding you've implemented sufficient security. That FDA guidance can be used to drive your cybersecurity documentation. (Again, not needed for 62034 compliance so you can postpone that work to focus on 62304).
NEVER give a reviewer access to your git server!

Seriously, they should never get to that level. At most, they may want to track a change request through implementation but you should always drive.