* fix(uploads): prevent cross-photo contamination from filename collisions and non-atomic writes (#931)
* test: pin the suffixed photo filename format in the NFD pipeline suite (#931)
* test: make the suffix-uniqueness check deterministic-in-practice (#931)
* fix(uploads): widen the anti-collision suffix to 48 bits (#931)
* fix(uploads): hide staging files from list() + share one watermark limiter process-wide (#931)
* fix(uploads): reclaim orphaned staging files + revalidate watermark settings in queued jobs (#931)
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Co-authored-by: Paul Nothaft <[email protected]>
New Settings → General toggle `Use original filenames on download` (off by
default). When on, single-photo downloads, bulk/selection zips, and per-event
archive zips surface `photos.original_filename` instead of the sanitized
storage filename. Storage paths are unchanged.
- Content-Disposition uses RFC 5987 (`filename=` ASCII + `filename*=UTF-8''…`)
so unicode camera filenames survive while header-injection bytes are stripped.
- Zip entries are deduplicated with a deterministic `_1` / `_2` suffix on
collision (folder structure preserved in archive zips).
- Pre-generated download-all zips and the in-memory setting cache are
invalidated when the toggle flips so the next download rebuilds with the
new names.
- Falls back to the storage filename whenever `original_filename` is null
(legacy uploads predating migration 062).
