The Minshall+French format is what macOS uses to store Unix symlinks on FAT and CIFS volumes. More details on the Minshall+French format can be found here:
The Linux CIFS implementation provides a 'mfsymlinks' mount option (which is off by default) that supports the Minshall+French format.
I believe Docker ...
You can use Access Control Lists for this. Run
chmod +a "USERID:deny:delete_child" DIRECTORY
to prevent the user USERID from deleting anything from the directory. To undo, run
chmod -a "USERID:deny:delete_child" DIRECTORY
PS: If you want to have it applied to current and future subfolders beneath DIRECTORY as well, use