How do I design my NodeJS app to have one config (per env) that can work for both K8S and locally in debugger?

Question

I've been using K8S for a year or so and continue to revisit a problem. My app is running in K8S and I now need to debug it. I have a NodeJS App that I'm asking about. But similar questions could be asked about Java SpringBoot apps (but this question is just for NodeJS).

I want to use my favorite IDE (IntelliJ or VSCode) to run the app but the app is currently getting it's configuration (inside K8S) using ConfigMaps and Secrets.

(Q) Is there a "best practice" or "pattern" that can be followed that supports the DRY principle and has configuration in one place that can be used for both K8S and when running locally.

Background

I have a NodeJS app that I decided to use ENVIRONMENT variables to hold configuration information because that worked well in IntelliJ IDE, in Docker and in K8S.

I used npm dotenv and created .env.local, .env.stage, .env.prod files to support running in different environments. This worked well enough until it was running in K8S and someone wanted to tweak the configuration and didn't believe that rebuilding the image was the best way to support this. Instead the K8S experts told me I should use ConfigMaps and Secrets, so I converted from the dotenv approach to use the K8S ConfigMaps and Secrets.

I kept the old .env files around just in case and I can use them but the source code no longer call uses dotenv package.

require('dotenv').config()
process.env.myConfigVariable

So I need to either add that code back to support debugging, or manually set the environment variables. I'm wondering if there is a better approach.

I have yaml files templates to make it easy to recreate the deployment from scratch if/when needed.

.env.local
deploy/
  helm/
  create-configmap.yaml
  create-secret.yaml
src/
  common/*
  appMain.js

Some of the approaches I've considered:

(a) Accept it and have two configs (one for local and one for K8S). Leave the code for dotenv but don't deploy a .env file when deploying to K8S.

(b) Run local k8s (like minikube or k3s) and use my ConfigMap and Secrets as I would with K8S. I then need to figure out how to connect from my IDE to the local K3S environment and open ports in the k3s environment to support this. Some solutions include: Bridge to Kubernetes, YouTube Video Remote Debugging in Kubernetes with Cloud Code, Debug Java Microservices in Kubernetes with IntelliJ, and I'm sure several others.

(c) Use a JSON config file instead of dotenv. For example, use a JSON config file for everything and map that to /app/config.json and that same config file can be used in both environments. I could have config-local.json, config-stage.json, and config-prod.json to support the different environments.

(d) You tell me. What's another way?

Thanks!