The video's hosted CDN URL was added to WebTorrent's `urlList`, but a
standalone hosted-file URL is only a valid BEP19 webseed for a SINGLE-file
torrent. For a multi-file torrent WebTorrent treats it as a base directory and
appends "<torrent name>/<file path>", producing a doubled URL that 404s on
every request — the flood seen on e.g. archive.org videos.
The CDN URL is no longer placed in urlList. It's forwarded separately as
`hostedUrlWebSeed` and attached post-metadata (handleTorrentStream) via
torrent.addWebSeed ONLY when the torrent is a single file, where the URL maps
directly to the file. Multi-file torrents get no file-pointing webseed, so no
flood. Magnet-declared `ws=` webseeds are unaffected (passed via urlList as
before). With CDN-first, dual-source videos play the CDN directly anyway, so
this only affects forced-torrent / URL-less paths.
Tests: a single-file torrent receives the hosted URL via addWebSeed; a
multi-file torrent does not. The single-file guard is mutation-verified.
Co-Authored-By: Claude Opus 4.8 <[email protected]>
