Route small images through in-memory receive instead of serialized disk
chunk-acks, and improve gallery hydration for local copies and pending
downloads so thumbnails display without minutes-long progress stalls.
Co-authored-by: Cursor <cursoragent@cursor.com>
Hydrate playable media after disk receive, relay file-announce to sibling
devices via account_sync, bind DM attachments to pre-allocated message ids,
and improve gallery retry/cancel UX with bounded parallel auto-downloads.
Co-authored-by: Cursor <cursoragent@cursor.com>