check for frozen_manifest argument and mout parent to container

This commit allows to use FROZEN_MANIFEST paths outside the main micropython directory, by mounting the parent directory of the manifest to the container. <img width="1903" height="233" alt="image" src="https://github.com/user-attachments/assets/805d99b2-8b93-4b27-8c08-d8e4c2add50d" />