- Convert to DNG / Copy as DNG: the encoded DNG must decode to the same raw
data, then goes through safe_file::write_new_unique (temp file, sync,
read-back, hard-linked to the first free <stem>.dng / -2 / -3 name, never
replacing a file). On failure no DNG is left, the photo is not relinked
and the raw copy is kept.
- Photo Merge writes its DNG the same way.
- Smart previews are written atomically; smart::is_valid (header + complete
JPEG) decides "built", has_smart_preview and the offline fallback, so a
proxy cut short is rebuilt (reported as `repaired`); moving proxies to a
new folder never deletes a good one in favour of a damaged copy and
copies across drives atomically.
Stacked on the #93 branch (shared lightcraft_catalog::safe_file helper).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>