A read-only lowerdir for the overlayfs causes permission issues

[Frontear]

Expected Result
Running darling shell compiled with a custom, read-only lowerdir=<path> should function correctly.

Actual Result
Paths from the lowerdir are brought up as read-only, making any commands that write to the filesystem fail with "Permission denied".

Steps To Reproduce

1. Compile darling with a custom directory specified at build-time
2. Attempt to run darling shell, then xcode-select --install
3. Permission Denied

System Information
NixOS 24.11 (I have confirmed this issue is possible on Arch Linux as well)

Software	Version
Linux Kernel	6.6.53
Darling	25afbc7

[Frontear]

Despite attempting to recursively add the write bit, it will still error out at random locations with Permission denied. The only fix is to either have a read-write lowerdir, or run darling shell as root (as in literally sudo darling shell), the latter being an extremely bad idea for many reasons.