Stop deleting App Group metadata and image files in getSharedImageData()
so retrieval is read-only while preserving the existing plugin API shape.
Document removed deletion paths in the iOS share target audit.
Store shared images as <shareId>.<ext> in the App Group container while
keeping the original filename in metadata, preventing on-disk collisions
without changing retrieval, deletion, or JS consumer behavior.
Generate a UUID per incoming share in the Share Extension, persist it
as sharedPhotoShareId in App Group metadata, and add [ShareTarget] logs
for receive/store/retrieve events without changing retrieval or deletion.
Document the Share Extension → App Group → main app flow, including
read/write/delete points, startup detection hooks, timing behavior,
and race conditions to support share-target reliability work.
