Adds complete k8s/ manifest tree: Namespace, VaultAuth + VaultStaticSecret
CRDs (VSO secret sync from Vault KV v2), API and UI Deployments and Services,
nginx Ingress with cert-manager TLS, MinIO StatefulSet with PVC and init Job,
and Alembic init container on the API Deployment for automatic schema
migrations. Includes .yamllint.yml config and validate-k8s Makefile target.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
