Your question is Version Control for Code and IaC. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You're setting up delivery pipelines for both application code and infrastructure changes. You want a simple way to keep them versioned together so deployments stay traceable and environment changes do not drift over time.
How do you manage version control for infrastructure and application code together?