Provide scripts for purs code generation

Provide plutus-playground-generate-purs and
marlowe-playground-generate-purs in the shell environment for
convenience.

shell.nix

@@ -3,10 +3,10 @@
 , config ? { allowUnfreePredicate = (import ./lib.nix).unfreePredicate; }
 , rev ? "in-nix-shell"
 , sourcesOverride ? { }
-, packages ? import ./nix { inherit crossSystem config sourcesOverride rev; }
+, packages ? import ./. { inherit crossSystem config sourcesOverride rev; }
 }:
 let
-  inherit (packages) pkgs plutus plutusMusl;
+  inherit (packages) pkgs plutus plutusMusl plutus-playground marlowe-playground plutus-scb;
   inherit (pkgs) stdenv lib utillinux python3 nixpkgs-fmt;
   inherit (plutus) haskell agdaPackages stylish-haskell sphinxcontrib-haddock nix-pre-commit-hooks;
   inherit (plutus) agdaWithStdlib;
@@ -57,6 +57,20 @@ let
     zlib
   ] ++ (lib.optionals (!stdenv.isDarwin) [ rPackages.plotly R ]));
 
+  plutus-playground-generate-purs = pkgs.writeShellScriptBin "plutus-playground-generate-purs" ''
+    rm -rf ./generated
+    ${plutus-playground.server-invoker}/bin/plutus-playground psgenerator generated
+  '';
+  marlowe-playground-generate-purs = pkgs.writeShellScriptBin "marlowe-playground-generate-purs" ''
+    rm -rf ./generated
+    ${marlowe-playground.server-invoker}/bin/marlowe-playground psgenerator generated
+  '';
+  plutus-scb-generate-purs = pkgs.writeShellScriptBin "plutus-scb-generate-purs" ''
+    rm -rf ./generated
+    cp ${haskell.packages.plutus-scb.src}/plutus-scb.yaml.sample plutus-scb.yaml
+    ${plutus-scb.server-invoker}/bin/plutus-scb psgenerator generated
+  '';
+
   # local build inputs ( -> ./nix/pkgs/default.nix )
   localInputs = (with plutus; [
     cabal-install
@@ -66,6 +80,9 @@ let
     hie-bios
     gen-hie
     hlint
+    marlowe-playground-generate-purs
+    plutus-scb-generate-purs
+    plutus-playground-generate-purs
     purs
     purty
     spago