Read-only host directory mounts, also over the C ABI
Read-only mounts. Python Bash.mount() and BashTool.mount() take
read_only=True, and Node mount() takes readOnly. Reads work; writes,
cp, mv, mkdir, rm and chmod inside the mounted tree fail, and
reset() keeps the protection.
bash.mount("/corpus", corpus, read_only=True)C ABI mounts. The C API can mount real host directories, through mounts
in the config or bashkit_mount and bashkit_unmount on a running session.
Each root must resolve under an allowed_mount_paths prefix and pass the
sensitive-path denylist. With no allowlist, every mount is rejected.
See Live mounts, C API, #2393 and #2371.