Create application configuration file

[Kaya-Sem]

Create a toml or .env config file to determine database names, paths, colors, etc

See the code near this line: https://github.com/Kaya-Sem/backpack-cli/blob/b27e4306afdf6610f1bf0a2ad75d17d0cd9d709c/src/database.py#L9

Also, look for the number of this issue in the project code base.