feat(deployment)!: split resources into deployment.gitea.resources and deployment.resources

The top-level `resources` value was applied to the Gitea container only, while its name suggested it covered the
whole pod. Kubernetes meanwhile supports pod-level resources, so a single ambiguous key can no longer express
both scopes.

Container-scoped limits and requests now live in `deployment.gitea.resources`, next to `deployment.gitea.env`,
and the new `deployment.resources` maps to the pod-level `resources` field. The pod-level block is only rendered
when set, because the field is not accepted by older API servers and would otherwise be rejected on clusters
that do not support it yet. The GOMAXPROCS derivation follows the container-scoped value and tolerates an unset
`deployment.gitea.resources`, which defaults to `null`.

The `deployment` section marker in `values.yaml` is restored as well. Without it the generated README lost its
`### deployment` heading and the manually maintained table of contents pointed at a non-existing anchor, which
made `markdownlint` fail.

BREAKING CHANGE: `resources` no longer exists. Use `deployment.gitea.resources` for container limits and
requests, or `deployment.resources` for pod-level resources. Installations that still set `resources` will fail
unless `checkDeprecation` is set to `false`.

Co-authored-by: Copilot <copilot@github.com>

unittests/helm/deployment/deprecations.yaml

@@ -46,6 +46,20 @@ tests:
     asserts:
       - failedTemplate:
           errorMessage: "`nodeSelector` does no longer exist. Please refer to the changelog and configure `deployment.nodeSelector` instead."
+  - it: fails when the removed `priorityClassName` value is set
+    set:
+      priorityClassName: high-priority
+    asserts:
+      - failedTemplate:
+          errorMessage: "`priorityClassName` does no longer exist. Please refer to the changelog and configure `deployment.priorityClassName` instead."
+  - it: fails when the removed `resources` value is set
+    set:
+      resources:
+        limits:
+          cpu: 100m
+    asserts:
+      - failedTemplate:
+          errorMessage: "`resources` does no longer exist. Please refer to the changelog and configure `deployment.gitea.resources` instead."
   - it: skips the deprecation checks when `checkDeprecation` is disabled
     set:
       checkDeprecation: false
@@ -59,6 +73,10 @@ tests:
           - 192.0.2.1
       nodeSelector:
         foo: bar
+      priorityClassName: high-priority
+      resources:
+        limits:
+          cpu: 100m
     asserts:
       - hasDocuments:
           count: 0