Explain how the rebuilt relibc proof and durable local patch carriers fit together so future upstream refreshes can reapply the compatibility work without relying on nested source state.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
vasilito
5aafb6475b