arr fleet: FrankBook-Pro is the sole deployment, all egress VPN-gated

FrankBook-Pro becomes the only *arr/qBittorrent deployment. Every fleet
container (qB + five arrs) now shares gluetun's netns, so all egress —
torrent, indexer APIs, metadata lookups — exits the WireGuard tunnel by
construction (AllowedIPs=0.0.0.0/0); the arrs' own ports publish on the
gluetun unit, none on the arr units themselves.

- dankserver/compose.yaml: remove the six arr services (the Aug 20 compose
  copy — never healthy, superseded; config dirs trashed on the host)
- dankclaw/Caddyfile + shared/homepage/services.json: arr vhosts and
  probes repoint 192.168.0.235 -> 192.168.0.112 (FrankBook-Pro)
- frankbook-pro units: five arrs join gluetun netns (Wants/After/Network);
  gluetun publishes 9696/8989/7878/8686/8787 alongside 8080/6881
- tests/frankbook_quadlet.bats: new VPN egress seam — every arr+qB unit
  must share gluetun's netns and publish no port; gluetun must publish the
  whole fleet's ports
- deploy-plan.py: gluetun changes carry the whole netns family (a gluetun
  recreation kills all six joiners); dankserver compose set loses the arrs
- AGENTS.md: deployment is complete only when unit tests AND the Playwright
  E2E suite both pass

frankbook-pro/prowlarr/quadlet/prowlarr.container

@@ -3,6 +3,10 @@
 # Install path is INSIDE the machine VM:
 #   /home/core/.config/containers/systemd/prowlarr.container
 #
+#
+# Joins gluetun's network namespace: all egress (indexer APIs, metadata
+# lookups) exits through the WireGuard tunnel; 9696 publishes on the
+# gluetun unit. Same-netns targets (qB, the arrs) are loopback addresses.
 # Arr on the Mac is grab-only: indexer + app-sync management lives here, the
 # arrs never auto-import media (the user reviews completed torrents in
 # /Volumes/COMPLETE/"Finished Torrents" and moves files manually into the
@@ -11,9 +15,12 @@
 # Config is migrated from dankserver's retired bare container
 # (tar-archived first, per the Phase 4 cutover note) — indexers and app
 # settings survive; stale host pointers (old qbit at 192.168.0.235:8080)
-# are re-pointed to the Mac's qbit via its API after first boot.
+# are re-pointed to loopback qBittorrent (127.0.0.1:8080, same netns) via
+# its API after first boot.
 [Unit]
 Description=Prowlarr (FrankBook-Pro)
+Wants=gluetun.service
+After=gluetun.service
 
 [Container]
 ContainerName=prowlarr
@@ -23,7 +30,7 @@ Environment=PGID=0
 Environment=TZ=America/Los_Angeles
 Environment=UMASK_SET=022
 Volume=/Volumes/COMPLETE/prowlarr-data:/config
-PublishPort=9696:9696
+Network=gluetun.container
 
 [Service]
 TimeoutStartSec=900