sendShareSet takes a title or an existing album (no new root; the first file threads after the album's newest event). Failed files carry the refusal for M_TOO_LARGE, M_FORBIDDEN and M_LIMIT_EXCEEDED in the result note. AlbumView mounts an Add files panel inside an open album.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>