The salvaged preflight (#67040) covers _send_file_attachment, but
send_multiple_images opened local files straight into discord.File with
no size check — one oversized image 413'd the whole chunk and dumped its
siblings into the per-image fallback. Preflight each local file against
the same boost-aware limit, skip oversized ones with a user-visible
notice, and still deliver the rest of the chunk.
Sibling-site widening for lobehub-scout salvage of PR #67040 (#50846).
Teknium
20a7a274d1