docs(media): point plan/journal/park paths at .media-campaign and NeedsProcessing

The campaign-artifact home moved (42bc482) but the copy-paste surfaces still
named the old ones, and a tool's usage block is exactly what an agent runs:

- scripts/media-shows.py, media-tv.py, media-tvdupes.py: usage examples wrote
  plans and journals at the array root. media-apply.py defaults its journal to
  <root>/media-relayout.jsonl, so any run copied from those lines re-creates
  the root-level clutter the vault now forbids. Each block now names
  /mnt/entropy/.media-campaign/ and says why --journal is explicit.
- media-shows.py: --park named the retired media-park; the pile is
  /mnt/entropy/NeedsProcessing/TVShows.
- Jellyfin.md: library-coverage law named /data/media-park; names the pile by
  its current path and records when it moved.
- Media TV Relayout.md: the runnable --park path named media-park.

bats: 822 seams green.

scripts/media-shows.py

@@ -78,10 +78,16 @@ one journal is one undo:
 
     python3 scripts/media-shows.py --root /mnt/entropy/TVShows \
         --enum /tmp/tv-enum.tsv --titles /tmp/jellyfin-tv.tsv \
-        --tvdb --tmdb --out /mnt/entropy/media-tv-plan.tsv \
-        --park /mnt/entropy/media-park/TVShows
-    python3 scripts/media-apply.py apply --plan /mnt/entropy/media-tv-plan.tsv \
-        --root /mnt/entropy --journal /mnt/entropy/media-tv-relayout.jsonl
+        --tvdb --tmdb --out /mnt/entropy/.media-campaign/media-tv-plan.tsv \
+        --park /mnt/entropy/NeedsProcessing/TVShows
+    python3 scripts/media-apply.py apply \
+        --plan /mnt/entropy/.media-campaign/media-tv-plan.tsv \
+        --root /mnt/entropy --journal /mnt/entropy/.media-campaign/media-tv-relayout.jsonl
+
+Every plan, journal and log lives in /mnt/entropy/.media-campaign/ — the array
+root holds libraries only. media-apply.py defaults its journal to
+<root>/media-relayout.jsonl, so pass --journal explicitly or the run puts the
+log back on the root.
 """
 import argparse
 import collections