develop: docs: user cp over mv. fix line break

Author: sid115

docs/introduction-to-nix/derivations.md

@@ -58,7 +58,7 @@ stdenv.mkDerivation {
   installPhase = ''
     # Install the compiled program into the output directory ($out)
     mkdir -p $out/bin
-    mv hello $out/bin/hello
+    cp hello $out/bin/hello
   '';
 }
 ```

docs/introduction-to-nix/nixos.md

@@ -92,6 +92,7 @@ It's primarily used for referencing options *within* the configuration.
 ## The Module System
 
 NixOS uses a powerful *module system*. A module is a Nix expression that declares:
+
 - **`options`**: What configurable parameters this module exposes.
 - **`config`**: How this module sets those parameters (and potentially other system parameters).
 - **`imports`**: Other modules to include.