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.