Fix recursive delete on macOS bind mounts

[Turbovadim]

Summary

• refresh the cached cap-std directory handle when metadata or symlink metadata lookups fail
• retry recursive directory deletes after refreshing the handle
• fall back to std::fs::remove_dir_all when cap-std recursive delete still fails on macOS bind-mounted volumes

Testing

• built and ran the patched wings image against the existing dev config on macOS rootless Docker
• reproduced the failure on current nightly by deleting a fresh copy of a nested pyzh-gate tree through /api/servers/:id/files/delete and observing {"deleted":0}
• verified the patched build returns {"deleted":1} and actually removes the directory on disk