feat(plex): expose tcp/32400 for remote access via a pinned LoadBalancer VIP

Remote Plex clients had no path in, for two measured reasons: Plex advertised
no remote connection at all (customConnections and ManualPortMappingMode both
ABSENT while PublishServerOnPlexOnlineKey=1), and its Service was ClusterIP, so
32400 had no off-cluster path. The L7 Gateway was NOT the problem -- it serves
Plex correctly (200, claimed=1, 401 on protected endpoints) -- but Plex clients
discover servers through plex.tv, not DNS, so an HTTPRoute cannot put this
server on a client's connection list.

Operator chose the native path over ADVERTISE_IP: Plex terminates its own TLS
with *.plex.direct and streams bypass the Envoy L7 hop.

Adds a hand-written non-catalog unit (the SD schema cannot express a
LoadBalancer Service or a pinned lbipam VIP), registered in render.py's
EXTRA_UNITS so --emit-waves places it in plex's own wave.

externalTrafficPolicy: Cluster, inheriting crafty's 8-day-outage lesson rather
than re-deriving it. Known consequence, documented: SNAT puts remote clients
inside ALLOWED_NETWORKS, so Plex meters them as LAN. Not an auth change.

Remote access does NOT work until the operator does two manual steps that
cannot live in this repo -- the WAN tcp/32400 forward and Plex's "manually
specify public port" toggle (no env var exists for it; verified NONE in the
image's init surface). runbooks/plex-remote-access.md is the procedure.

Touches clusters/** -- a sensitive path -- so the approval-policy stage will
block pending an operator /approve-override.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>

apps/wave-0/kustomization.yaml

@@ -18,6 +18,7 @@ resources:
 - pihole-oauth2-proxy-credentials.sops.yaml
 - pihole.yaml
 - plex-claim-secret.sops.yaml
+- plex-remote.yaml
 - plex.yaml
 - qbittorrent-bootstrap-secret.sops.yaml
 - qbittorrent-oauth2-proxy-credentials.sops.yaml