`savePhotoToDevice` previously buffered the full image through JS as a
Blob on every platform before clicking <a download>. On cellular this
added ~5s of dead air between the button press and the browser's
download dialog, prompting users to re-click and produce duplicate
downloads (#554 follow-up, post-#556).
The blob round-trip is only required for the iOS Web Share path
(`navigator.share({files})` needs File objects in hand). On Android and
desktop the browser can fetch the download URL itself and show its own
progress in the notification shade — instantly. So iOS keeps the
existing flow; everywhere else gets a direct anchor navigation.
The new `triggerDirectDownload` helper uses `api.getUri()` so the path
also works in split-origin deployments (where the existing hardcoded
`/api/...` pattern used by `downloadAllPhotos` would 404).
Tests updated: Android / desktop / regular-Mac branches now assert that
`fetchPhotoBlob` is NOT called and `triggerDirectDownload` is invoked
with a `/gallery/{slug}/download/{id}` URL. iOS tests unchanged.
Paul Nothaft
04795219a0