feat: add ServiceAccounts for poimen-memory/kmsvc/immich operator Roles

Bind each service's operator Role to a ServiceAccount alongside the
existing oidc:*-admins Group, and wire serviceAccountName into the
pods we control (immich-server, immich-machine-learning,
management-service). poimen-memory's Deployment lives in its own
repo/ArgoCD app, so its SA is created here but not yet wired to a pod.

k8s/apps/messaging/management-service/templates/deployment.yaml

@@ -13,6 +13,7 @@ spec:
       labels:
         app: management-service
     spec:
+      serviceAccountName: kmsvc
       topologySpreadConstraints:
         - maxSkew: 1
           topologyKey: kubernetes.io/hostname