Create an endpoint /health that returns the health status of a namespace, workload, service, or app.
Health should be derived from metrics (success/error rates, latency), proxy sync status, and Kubernetes readiness.
This will allow dashboards or troubleshooting tools to visualize current operational health.

Deliverables:

• /health?namespace=&workload=&service=&app= endpoint.

• Health computation logic for each entity type.

• Unit tests and example responses.