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  copy — never healthy, superseded; config dirs trashed on the host)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/readarr/quadlet/readarr.container

@@ -3,6 +3,9 @@
 # Install path is INSIDE the machine VM:
 #   /home/core/.config/containers/systemd/readarr.container
 #
+#
+# Joins gluetun's network namespace: all egress exits through the WireGuard
+# tunnel; 8787 publishes on the gluetun unit.
 # Grab-only: no media binds; config migrated from dankserver's retired
 # bare container.
 #
@@ -11,6 +14,8 @@
 # of a broken 1.x nightly for Readarr; the pin avoids surprises.
 [Unit]
 Description=Readarr (FrankBook-Pro)
+Wants=gluetun.service
+After=gluetun.service
 
 [Container]
 ContainerName=readarr
@@ -20,7 +25,7 @@ Environment=PGID=0
 Environment=TZ=America/Los_Angeles
 Environment=UMASK_SET=022
 Volume=/Volumes/COMPLETE/readarr-data:/config
-PublishPort=8787:8787
+Network=gluetun.container
 
 [Service]
 TimeoutStartSec=900