GetEnv reads a file expected to represent a collection of KEY=value in
standard shell environment variable format - ie, key usually in all upper
case no spaces and words separated by underscore, value can have any separator, but usually
comma, for an array of values.
LookupEnv returns the raw string value associated with a provided key name, used as a custom
environment variable loader for go-simpler.org/env to enable .env file loading.