docs(vault): the scan pages name their drivers, and a class no screen sees

Plex.md and Jellyfin.md keep every law and point at the driver that now carries
them, so the procedure has one owner and the pages keep the failure signatures.
Jellyfin.md also records where `jellyfin.db` actually lives on this host (the
quadlet's config bind, not the stock path) and demotes `immutable=1` on the
`ApiKeys` read to the `-shm` fallback, because the database is WAL and
`immutable` skips the log. Plex.md gains the live section keys and the
`scanned_at == scannedAt` fact.

Media Relayout.md's hand-off after an apply names both drivers and states the
ordering law: Jellyfin first and alone, since its one door walks every library
while Plex forks a scanner per section, and the array is what both share.

Media Duplicate Prune.md gains the guard the 2026-11-04 hold taught: 32 files
carrying real film titles were 8-20-second h264 clips (49 MiB, 25 of them in a
`_release-group watermarks/` folder), invisible to every duplicate screen
because nothing shares their size and the feature-length guard hides them. The
census that finds the next batch is a duration floor, not a hash.

serverAppConfigs-docs/Dankserver/Media Relayout.md

@@ -99,12 +99,17 @@ interrupted apply still replays the batch and resumes with nothing lost. Batch 1
 is the old behaviour; the only reason to name it is debugging, because on the
 spinning array it spends most of a large apply's wall time in fsyncs.
 
-After it lands, both servers need a scan or the change is invisible. [[Plex]] and
-[[Jellyfin]] own the exact requests; two laws hold at this step: `204` is
-acceptance and anything else queued nothing — re-issue the identical request
-rather than diagnosing — and ONE accepted refresh is the whole procedure, because
-a second while a scan runs moves `Scan Media Library` to `Cancelling` and every
-later `204` is accepted and then discarded.
+After it lands, both servers need a scan or the change is invisible. The two
+drivers are the doors — `scripts/media-refresh-jellyfin.py trigger` then `… wait`,
+and only after it settles, `scripts/media-refresh-plex.sh trigger --library <key>`
+with `… status --library <key> --after $(stat -c %Y <journal>)` as the poll. Run
+them in that order and never together: Jellyfin's only door walks every library,
+every Plex section forks its own scanner walk, and the array is the bottleneck
+both servers share. [[Plex]] and [[Jellyfin]] own the laws behind the drivers; two
+of them decide this step: `204` is acceptance and anything else queued nothing —
+re-issue the identical request rather than diagnosing — and ONE accepted refresh is
+the whole procedure, because a second while a scan runs moves `Scan Media Library`
+to `Cancelling` and every later `204` is accepted and then discarded.
 
 ### Proving the move landed