Document Dogu V3 artifacts and their relationships

[henry-bobka]

Document the core artifacts of a Dogu V3 and how they work together:

• Explain the Helm chart as the leading Dogu package: Chart.yaml, chart values and schema, companion files, and templates/.
• Cover the CES integration resources: AuthRegistration, Exposition, service accounts, and Warp Menu.
• Map how former dogu.json responsibilities are moved or removed (field by field), linking the owning CRDs/APIs rather than implementation.
• Note the risks of renaming Kubernetes resources (data loss, credential re-issue).