media stack: shared /data/media layout, promote sonarr/radarr/jellyfin/jellyseerr

- Promote sonarr, radarr, jellyfin, jellyseerr from _dev
- qBittorrent, Sonarr, Radarr, Lidarr, Readarr, Whisparr mount /data/media
  at /media so paths match across containers (no remote path mappings,
  hardlinks work); downloads go to /media/downloads/prowlarr
- Jellyfin: drop photos (use Immich) and unused internal network, rewrite README
- Jellyseerr: add TZ, document container hostnames and root folders

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

jellyseerr/compose.yaml

@@ -0,0 +1,19 @@
+services:
+  jellyseerr:
+    image: ${JELLYSEERR_IMAGE:-ghcr.io/hotio/jellyseerr:release}
+    restart: ${JELLYSEERR_RESTART:-unless-stopped}
+    volumes:
+      - ${VOL_PATH:-/data}/jellyseerr/config:/config
+    environment:
+      - PUID=1000
+      - PGID=1000
+      - UMASK=002
+      - TZ=${TZ:-America/Vancouver}
+    ports:
+      - "${JELLYSEERR_PORT:-5055}:5055"
+    networks:
+      - proxy
+
+networks:
+  proxy:
+    external: true