v3.7.6 — reliability fix for repeated copies with deduplication

Bug Fixes

• On copy-on-write filesystems (btrfs, XFS, APFS), repeating a copy no longer re-links a file that is already present at the destination against itself — already-present files are now left untouched, so re-runs are a clean no-op. Recommended update for anyone copying to btrfs / XFS / APFS. (ext4 / NTFS / HFS+ were unaffected.)