Go 1.24 introduced stricter checks for os.DirFS (via os.Root), which causes failures when /etc/passwd or /etc/group are absolute symlinks pointing outside the mount root (common in NixOS).
This patch introduces a helper that detects absolute symlinks and resolves them relative to the rootfs before opening, preventing the 'path escapes from parent' error.
Fixes#12683
Signed-off-by: Paulo Oliveira <paulo.hco47@gmail.com>