Add media-apps stack to ArgoCD

Why:
The media stack (jellyfin plus the sonarr/radarr/prowlarr/bazarr/nzbget/
jellyseerr apps) runs in the media-apps namespace but is deployed out-of-band
by terraform-k8s rather than GitOps. Bringing it under ArgoCD makes the stack
declarative, self-healing, and consistent with every other cluster workload,
and prepares terraform-k8s to drop the media-apps config.

How:
- Add a media AppProject scoped to the media-apps namespace and a media-apps
  ApplicationSet that renders one Application per app plus a shared foundation.
- Add a shared media-apps foundation (namespace, media-apps-vault-reader
  ServiceAccount, default VaultAuth on k8s/au/syd1, and the RWX movies/tvseries
  library PVCs) that the whole stack mounts.
- Add per-app kustomize base and au-syd1 overlay for jellyfin and the six *arr
  apps, using plain resource names (jellyfin, sonarr, ...) with fresh PVCs.
- Deploy jellyfin from the jellyfin-ha fork (Redis transcode store, RWX
  transcode scratch) wired to the shared movies/tvseries library PVCs, keeping
  the intel iGPU nodeSelector and gpu.intel.com/i915 request.
- Source API keys and nzbget credentials through VSO VaultStaticSecrets from
  kv/service/media-apps/<app>; expose each app via a traefik-internal Gateway
  and HTTPRoute at <app>.k8s.syd1.au.unkin.net.
- Register the media project and applicationset in the argocd bootstrap
  kustomizations.

apps/base/media-apps/kustomization.yaml

@@ -0,0 +1,10 @@
+---
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+
+resources:
+  - namespace.yaml
+  - serviceaccount.yaml
+  - vaultauth.yaml
+  - pvc_movies.yaml
+  - pvc_tvseries.yaml

apps/base/media-apps/namespace.yaml

@@ -0,0 +1,5 @@
+---
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: media-apps

apps/base/media-apps/pvc_movies.yaml

@@ -0,0 +1,16 @@
+---
+# Shared movies library, read-write-many across the *arr stack and jellyfin.
+# Greenfield-empty: a fresh CephFS volume, not the puppet mediafs library.
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: movies
+  namespace: media-apps
+spec:
+  accessModes:
+    - ReadWriteMany
+  resources:
+    requests:
+      storage: 500Gi
+  storageClassName: cephfs-raid5-retain
+  volumeMode: Filesystem

apps/base/media-apps/pvc_tvseries.yaml

@@ -0,0 +1,16 @@
+---
+# Shared tvseries library, read-write-many across the *arr stack and jellyfin.
+# Greenfield-empty: a fresh CephFS volume, not the puppet mediafs library.
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: tvseries
+  namespace: media-apps
+spec:
+  accessModes:
+    - ReadWriteMany
+  resources:
+    requests:
+      storage: 500Gi
+  storageClassName: cephfs-raid5-retain
+  volumeMode: Filesystem

apps/base/media-apps/serviceaccount.yaml

@@ -0,0 +1,12 @@
+---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: media-apps-vault-reader
+  namespace: media-apps
+  labels:
+    app.kubernetes.io/name: vault-reader
+    app.kubernetes.io/component: service-account
+  annotations:
+    vault.hashicorp.com/auth-method: kubernetes
+automountServiceAccountToken: true

apps/base/media-apps/vaultauth.yaml

@@ -0,0 +1,18 @@
+---
+apiVersion: secrets.hashicorp.com/v1beta1
+kind: VaultAuth
+metadata:
+  name: default
+  namespace: media-apps
+spec:
+  allowedNamespaces:
+    - media-apps
+  kubernetes:
+    audiences:
+      - vault
+    role: media-apps
+    serviceAccount: media-apps-vault-reader
+    tokenExpirationSeconds: 600
+  method: kubernetes
+  mount: k8s/au/syd1
+  vaultConnectionRef: vso-system/default