Add a new module for Visual Studio Code configuration including
default extensions (nix-ide, markdown-all-in-one, prettier) and
nixd/nixfmt settings. Enable vscode on 14900k, t2mbp, and uConsole
hosts with additional extensions.
Also clean up unfree predicate logic in ideapad configuration.
Refactor `modules/desktop/options.nix` to improve code readability through
consistent indentation and whitespace management. Simplified the
conditional logic for `home-manager.extraSpecialArgs` to remove
unnecessary complexity.
Clean up host configurations by removing commented-out code, removing
unnecessary whitespace, and flattening nested attribute sets into
single-line declarations where appropriate.
Olivier