Detect drifts between the manifest and its live Kubernetes resources

[chotiwat]

Description

This PR aims to address #1095 by performing a dry-run, server-side apply of the manifest during planning, which allows Terraform to detect any changes to the Kubernetes resources managed by the Helm release.

Mini Changelog

• Introduce a new resources attribute which tracks Kubernetes resources managed by the deployed Helm release
  • The attribute is a map of resource key to resource JSON string.
  • Fields managed by kube-controller-manager or updated via subresource APIs (e.g. /status and /scale) are removed to avoid perpetual drifts.
  • Sensitive values are redacted like in the manifest attribute.
  • Fields like uid, creationTimestamp, resourceVersion, and managedFields are scrubbed to prevent the inconsistent final plan issue.
• Generate a new version of resources during planning using a dry-run, server-side apply for diffing
• Add acceptance tests to confirm that Kubernetes resources are reconciled when they are modified or deleted

Acceptance tests

• [x] Have you added an acceptance test for the functionality being added?

Release Note

Release note for CHANGELOG:

`resource/helm_release`: add `resources` map attribute to allow drift detection against live kubernetes resources [GH-1095](https://github.com/hashicorp/terraform-provider-helm/issues/1095)

References

https://github.com/hashicorp/terraform-provider-helm/issues/1095 https://github.com/hashicorp/terraform-provider-helm/issues/1239

Community Note

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