docs(media): a scan request belongs to the server's own page

Media Relayout.md hit the vault's 500-line gate the moment the tvdb contract
landed, and the fat in it was not the new text: the Plex and Jellyfin scan
blocks (35 lines) sat inside the relayout procedure even though they are the
way you talk to those servers after ANY change, and two Laws bullets repeated
the same facts a third time. Both blocks now live on [[Plex]] and
[[Jellyfin]]; the relayout page keeps the two laws an operator needs at that
moment — 204 is acceptance and anything else queued nothing, and one accepted
refresh is the whole procedure, because a second moves `Scan Media Library` to
`Cancelling` and every later 204 is discarded.

Same pass, the dead numbers the vault's own law says to destroy: an applied
music pass's date, an applied audiobook pass's move/park counts, and the 146
sweep stragglers of one specific first sweep. The laws they taught stay.

490 lines, `bats tests/docs_completeness.bats` 6/6 (length violation gone,
link integrity clean).

serverAppConfigs-docs/Dankserver/Jellyfin.md

@@ -182,6 +182,48 @@ scripts/jellyfin-providers.sh verify    # plugin + key LENGTHS, never key bytes
 2. Set metadata/language preferences (`LANG=en_US.UTF-8` pinned in the unit).
 3. Configure clients to use `http://192.168.0.235:8096` or the guarded vhost.
 
+## Triggering a scan
+
+The scan key lives in `~/.config/secrets/jellyfin` (mode 600; the same value is
+`JELLYFIN_API_KEY` in the ignored `dankserver/.env`). It rides a mode-600 curl
+config, never a header argument, in the `MediaBrowser` form: 12.4 authenticates
+only `Authorization: MediaBrowser Token="…"` and refuses a bare `X-Emby-Token`
+for every key, valid or not. Before believing a 401, prove the key against the
+server's own table — `select count(*) from ApiKeys where AccessToken = ?` on
+`jellyfin.db` opened `mode=ro&immutable=1`. The backslashes below matter:
+
+```bash
+umask 077
+{ printf 'header = "Authorization: MediaBrowser Token=\\"%s\\""\n' \
+    "$(cat ~/.config/secrets/jellyfin)"
+  echo 'url = "http://127.0.0.1:8096/Library/Refresh"'
+  echo 'request = "POST"'; } >/tmp/jf.hdr
+curl -s -K /tmp/jf.hdr -o /dev/null -w "jellyfin scan: %{http_code}\n"
+shred -u /tmp/jf.hdr
+```
+
+`204` is acceptance; anything else queued no scan, so re-issue the identical
+request instead of diagnosing. A `401` from a key that answers `200` on a
+hand-typed request is this block's quoting, not the server: bash `printf`
+collapses `\"` to `"`, curl ends the quoted value at that quote, and Jellyfin
+receives `Authorization: MediaBrowser Token=` with nothing after it (`\\"` answers
+204, `\"` answers 401 — both run on this host).
+
+One accepted refresh is the whole procedure. A second one while a scan runs moves
+`Scan Media Library` to `Cancelling`, and once the runner holds `Cancelling` every
+later `204` is accepted and then discarded — the status code stops meaning
+anything. The fix is `systemctl --user restart jellyfin.service` (never
+`deploy.sh`: that runs the never-tested metadata-view cutover), one POST after
+health answers, and then believe `ScheduledTasks` State at 130 % CPU, not the
+response code.
+
+**A scan that must see a new folder has to be recursive.** `POST /Library/Refresh`
+is the incremental pass, and inotify does not cross a rootless podman bind, so
+folders created on the host stay invisible to it. The move is
+`POST /Items/{id}/Refresh?Recursive=true` (204) per library, the id from
+`GET /Library/VirtualFolders` — its field is `ItemId`, not `Id` — and that same
+record's `RefreshStatus` is the progress read.
+
 ## See Also
 
 - [[Plex]] — co-resident media server on the same volume