`dnsConfig` was a top-level value although it exclusively configures the pod spec of the Gitea Deployment. With
`affinity` and `env` already moved into the `deployment` dict, keeping `dnsConfig` at the root level leaves the
Deployment configuration split across two places and makes it harder to see which values end up in the rendered
pod spec.
Moving it into the `deployment` dict continues the consolidation of Deployment-scoped values and keeps the
values structure predictable for the remaining pod-level settings.
A deprecation check is added so that existing installations fail fast with an actionable error message. Without
it, a custom DNS configuration would be dropped silently, which typically surfaces much later as unexplained
name resolution failures inside the Gitea pod.
BREAKING CHANGE: `dnsConfig` no longer exists. Use `deployment.dnsConfig` instead. Installations that still set
`dnsConfig` will fail unless `checkDeprecation` is set to `false`.
Co-authored-by: Copilot <copilot@github.com>