Add description to script

Just some metadata that can be useful in various contexts like enterShell for example.

docs/scripts.md

@@ -57,3 +57,26 @@ Entering shell ...
   "foo": "1"
 }
 ```
+
+Scripts can also have an optional description, which can be used in your `enterShell`.
+
+```nix title="devenv.nix"
+{ pkgs, ... }:
+
+{
+  scripts.silly-example.exec = ''
+    ${pkgs.curl}/bin/curl "https://httpbin.org/get?$1" | ${pkgs.jq}/bin/jq '.args'
+  '';
+  scripts.silly-example.exec = ''simple example script'';
+  enterShell = ''
+      echo
+      echo 🦾 Helper scripts you can run to make your development richer:
+      echo 🦾
+      sed -e 's| |••|g' -e 's|=| |' <<EOF | column -t | sed -e 's|^|🦾 |' -e 's|••| |g'
+      ${lib.generators.toKeyValue {} (lib.mapAttrs (name: value: value.description) config.scripts)}
+      EOF
+      echo
+    '';
+}
+```
+

src/modules/scripts.nix

@@ -1,5 +1,8 @@
-{ pkgs, lib, config, ... }:
-
+{ pkgs
+, lib
+, config
+, ...
+}:
 let
   types = lib.types;
   scriptType = types.submodule ({ config, ... }: {
@@ -8,6 +11,11 @@ let
         type = types.str;
         description = "Bash code to execute when the script is run.";
       };
+      description = lib.mkOption {
+        type = types.str;
+        description = "Description of the script.";
+        default = "";
+      };
     };
   });
   # lib.hiPrioSet: prioritize scripts over plain packages