Consider using a configuration file inside xdg config dir

[cortsf]

• Specify computer name
• Specify dotfiles path
• Tweak colors/theme

Set up variables using (in this particular order):

1. .env file provided by calling jkl with a --jkl-config <env_file> argument
2. Xdg config file: ~/.config/jkl/cofig.env
3. Environment variables
4. Defaults

• Don't trust and source ~/.config/jlk/jkl.env directly
• Don't just filter out irrelevant declarations from ~/.config/jkl/jkl.env, think of malicious variables like: JKL_COMPUTER_NAME="$(rm -rf *)"
• Allow using variables (as in JKL_COMPUTER_NAME="$HOME/.dotfiles") but prevent execution of code (as in JKL_COMPUTER_NAME="$(rm -rf *)"). Just disallowing the usage of $ (as in eval "$(cat "$HOME/.config/jkl/jkl.env" | grep -E "^JKL_COMPUTER_NAME=\"[^\$]* *$|^JKL_FLAKE_DIR=\"[^\$]* *$")") is not an ideal solution
• Keep codebase as dumb and simple as possible and do not introduce any dependencies.