feat(infra): replace Temporal dev server with production deployment

- Replace temporalio/temporal (SQLite dev server) with temporalio/server
  backed by CNPG PostgreSQL (hightower-temporal-db)
- Add schema init Job using temporalio/admin-tools
- Add separate temporalio/ui deployment for the web dashboard
- Remove namespace.yaml — namespace is managed by the cluster repo
- Remove ensureNamespace() from K8s orchestrator

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

infra/kustomization.yaml

@@ -1,8 +1,7 @@
 apiVersion: kustomize.config.k8s.io/v1beta1
 kind: Kustomization
 resources:
-  # Shared infrastructure (namespace, Temporal, PVCs)
-  - ../apps/cli/infra/k8s/namespace.yaml
+  # Shared infrastructure (Temporal + PostgreSQL, PVCs)
   - ../apps/cli/infra/k8s/temporal.yaml
   - ../apps/cli/infra/k8s/workspaces-pvc.yaml
   # API server