[common]: add generic annotations field for resource-level metadata.annotations

[rekup]

What this PR does:
Adds a generic annotations field to the common chart so top-level metadata.annotations can be set on generated Job, CronJob, Deployment, StatefulSet, and Service resources. This enables use cases like Helm hook annotations (helm.sh/hook, helm.sh/hook-weight, helm.sh/hook-delete-policy) that were not previously possible, since the existing controller.extraAnnotations only targets the Pod template, not the resource itself.

Changes:

• New library.annotations helper in templates/helpers/_labels.tpl (wraps the existing library.mapify helper with an annotations: key).
• annotations wired into _job.yaml, _cronjob.yaml, _deployment.yaml, _statefulset.yaml, and _service.yaml.
• values.schema.json updated to allow annotations under controller and services.*.
• Documentation and examples added to values.yaml.
• ci/values.test.yaml extended to exercise the new field.
• Chart.yaml: version bumped to 12.11.0, artifacthub.io/changes entry added referencing [common] Add generic annotations to control Helm hooks/execution order #189.
• README.md regenerated via make helm-docs (version badge only).

Which issue this PR fixes
fixes #189

Notes for Reviewer:

• annotations (new) vs. extraAnnotations (existing): the former sets metadata.annotations on the resource itself, the latter sets spec.template.metadata.annotations on the Pod template. Please double-check naming makes this distinction clear.
• Templating inconsistency (now documented in values.yaml): the new controller.annotations/services.*.annotations (and the existing controller.extraAnnotations) render each value through tpl against the root context (via library.mapify), so e.g. "{{ .Release.Name }}" gets expanded. ingresses.*.annotations and pvcs[].annotations predate this feature and render values as-is via a plain toYaml (no tpl). I deliberately did not change the Ingress/PVC behavior to add templating, since that would be a silent, potentially breaking behavior change for any existing user who has literal {{ ... }}-looking strings in those annotations today. The new fields instead follow the already-established extraAnnotations/extraLabels convention. Added comments in values.yaml on all four annotation fields cross-referencing this difference.

Checklist:

• Pull Request title in format [chart]: Changed Something
• Updated documentation in the README.md.gotmpl file and executed helm-docs
• Chart Version bumped
• All commits are signed-off

[wthhub]

Looks good, thanks for contributing!