nix: run the review classifier in a container of its own when a host enables it

deploy.review-classifier.enable (off by default, not derived from
allSwarmServices) puts swarm-review-classifier in its own network
namespace on the bridge, with claude-code and the daemon. A host unit
copies the classifier's store leaf into the container; the daemon reads
its queue client secret and the API key from the store with it.

- glue-bao-tls mints the review-classifier leaf; swarm-bao writes the
  swarm-review-classifier role, reading exactly the API key path and the
  classifier's queue client secret; swarm.nix reserves its CN.
- glue-review-classifier-oidc-client registers the machine client where
  authelia runs, and the publisher carries its secret to the store.
- swarm-nats passes the client id to the responder as
  --review-classifier-client.
- Where the host runs a hive-tier collector, claude exports its metrics
  there; the daemon adds the repo and the PR to the resource attributes.
- module-eval: the new grant and leaf (bao-grants, now sixteen granting
  units), the container's presence and its unit (core-toggle), and the
  client registration and publishing (secret-publisher).

nix/host-modules/default.nix

@@ -39,6 +39,7 @@
     ./glue-nats-bao-identity.nix
     ./glue-nats-oidc-client.nix
     ./glue-queue-agent-credential.nix
+    ./glue-review-classifier-oidc-client.nix
     ./glue-secret-publisher-bao-identity.nix
     ./glue-swarm-bao-otel-oidc-client.nix
     ./glue-swarm-otel-oidc-client.nix
@@ -47,6 +48,7 @@
     ./swarm-bao-service.nix
     ./swarm-bao.nix
     ./swarm-ci-runner.nix
+    ./swarm-review-classifier.nix
     ./swarm-secret-publisher.nix
     ./swarm-nats-service.nix
     ./swarm-nats.nix