Kickstart rewrite

[nikero41]

This pull request primarily focuses on cleaning up configuration and theme files, as well as updating license information. The most significant changes are the removal of iTerm2 color scheme files, updates to configuration files for development tools, and a correction to the copyright year.

Configuration and theme cleanup:

• Removed iTerm2 color scheme files coolnight.itermcolors and mellow.itermcolors from the extras/iterm2 directory. [1] [2]
• Deleted the .luarc.json file, which was used for Lua language server configuration.
• Simplified .neoconf.json by removing the neodev configuration block.
• Cleaned up config_files/.selene.toml by removing the std = "neovim" setting and some specific rule allowances.

Other changes:

• Updated the copyright year in the LICENSE file from 2023 to 2026.