Release standalone binaries

## Problem

current release `build_release.sh` produces a self-contained folder with the [target binary and its dependencies](https://docs.microsoft.com/en-us/dotnet/core/deploying/deploy-with-cli#self-contained-deployment-with-third-party-dependencies) (run-time, etc).

However, a single binary would be of interest for simpler portability. This is done by [LINQPad](https://www.linqpad.net), for example

## Task

publish single-binary self-contained releases