Manipulate appsettings.json

When you publish to AWS and choose Fargate, a container image is built locally and deployed to AWS.
Then the corresponding cluster, service, tasks, task definition, and load balancer get deployed.
And it all works.

But what happens to the settings from appsettings.json? How are they deployed and how can I alter them?
The ideal scenario would be to either:
1) put them one by one in "environment" inside Task Definition.
2) create .ENV file, save it in an S3 bucket, and reference the file from Task Definition.

In this case everything would be according to the recommendations and it would be easy to change the settings as we see fit.

Start with the AWS Fargate publishing workflow described in the issue, focusing on how the container image and ECS task definition are generated. Review the task definition's environment handling and the deployment steps. Done means appsettings.json values can be deployed as task-definition environment entries or through an S3-hosted .ENV file and then changed as requested.

Written by the indexing model from the issue text.