Use entry.file_type() instead of entry.metadata().file_type() to avoid
unnecessary stat syscalls. The file_type() method uses the cached d_type
field from the readdir() syscall when available, eliminating the need
for additional filesystem access.
This matches the behavior described in https://github.com/NixOS/nix/pull/13412
where readDir should only read directory entries without stat'ing each file.
Change-Id: I8983f84a7cff28b2c892d5829b9880ed22be4389
Reviewed-on: https://cl.snix.dev/c/snix/+/30596
Reviewed-by: Florian Klink <flokli@flokli.de>
Tested-by: besadii
ba0a01e7aa