terraform-provider-flux VS kustomize-controller

IMO, a better approach would be to provision your cluster using terraform, then do cluster operations using a GitOps tool, such as GitOps Toolkit (Flux v2) - https://toolkit.fluxcd.io/. You can point multiple clusters to the same repo and they are going to apply and reconcile the desired state for all or your clusters if needed. There’s also a Flux terraform provider - https://github.com/fluxcd/terraform-provider-flux, bootstrap flux then let it do its job.

You could try this: https://github.com/fluxcd/terraform-provider-flux

The combination of the tools I mention at the end would likely satisfy all of your needs. kustomize-controller, which is the part of flux that deploys your application, has the ability to check if the deployment's health check failed. I assume it also has the ability to rollback (or at least it easily might in the future). it also tracks the state of the applied objects so that it can delete objects that are not used anymore.