feat: Add `nvim-dap` for better debugging

[RiddleMan]

https://github.com/mfussenegger/nvim-dap

[RiddleMan]

https://github.com/mfussenegger/nvim-dap/wiki/Debug-Adapter-installation
mxsdev/nvim-dap-vscode-js#63 - here how to configure for each lang

https://github.com/mrcjkb/rustaceanvim - here's the setup for Rust (not only dap)

https://github.com/Weissle/persistent-breakpoints.nvim - persistent breakpoints

https://github.com/rogalmic/vscode-zsh-debug - add debugging for zsh