feat(media): measure a series per episode, and let the tag outrank a borrowed id

media-tvdupes.py censuses a TV library by episode key and never by folder. 10 of
the 25 shows that looked duplicated in the 2026-11-02 census held complementary
halves (Game of Thrones Complete carries no S01 or S08, Modern Family S05 is the
only copy of season 5), so a folder-level verdict would have staged some 340 GB
of unique episodes to recover 54 GiB of true copies.

Show identity comes from the folder's [tvdbid-N] tag, from the tvshow.nfo the
metadata view exposes, or from an operator --ids map. A derived id that
contradicts a tag is dropped and reported, never unioned: Jellyfin's provider
table carries a 2026 special's id on the folder tagged [tvdbid-73838], and
unioning the two makes one show of a 2000 series and a 2026 special whose bigger
files then dominate the original's pilot. Files named by an id key only when the
server's own episode table (the --witness) names them, so a bare number is never
mistaken for an episode.

Seam: tests/media_tvdupes.bats — 12 assertions on which files land in the plan
and which the tool refuses to touch, on a synthetic library.

serverAppConfigs-docs/index.md

@@ -52,7 +52,7 @@ is a locator: one row, one clause, no numbers.
 | [[Jellyfin]] | Jellyfin on Dankserver: quadlet unit, overlay metadata view, provider keys, ports, access, transcode status. |
 | [[mariadb]] | The MariaDB backend for RomM: quadlet unit, network alias, env-file secret handling, and the backup path. |
 | [[Media Audiobook Relayout]] | Re-filing /mnt/entropy/Audiobooks by Plex's chapter rows: narrator shelves, no renumbering, the refusals. |
-| [[Media Duplicate Prune]] | Find and hold duplicate films on the entropy array: the hash ladder, the keep rules, the guards, the purge. |
+| [[Media Duplicate Prune]] | Find and hold duplicate films and series on the array: the screen, per-episode rule, guards, purge. |
 | [[Media Metadata View]] | The SSD-backed overlay the two media servers read and write: shape, guards, commands, laws, rollback. |
 | [[Media Music Relayout]] | Re-filing /mnt/entropy/Music by Jellyfin's tag rows: the census, the album key, the refusals. |
 | [[Media Relayout]] | Census, plan and apply the movie, TV, music and audiobook libraries: the gates, the refusals, the rollback. |