The comments for the 'ErrCertConfigEmpty' variable in error.go contained a typo. This has been corrected to more accurately reflect the error that is returned when a TLS listener is configured without setting certificate or key paths.
All source code files as well as README.md, .gitignore, and various configuration files have been updated with an SPDX license identifier, changing license from CC0-1.0 to MIT. The copyright year has been updated to 2023, and the copyright holder's email address has been corrected from 'winni@neessen.dev' to 'wn@neessen.dev'. An MIT license text file has been additionally added.
This commit introduces the creation of the core server and its components: config loading mechanism, listener setup, and error handling. The provided configuration allows the server to run different types of listeners. Additionally, it includes robust log-level settings to facilitate debugging and operational transparency.