feat: add initial parser data structure & test

Signed-off-by: Konstantin Fickel <mail@konstantinfickel.de>

flake.nix

@@ -110,9 +110,10 @@
         # It is of course perfectly OK to keep using an impure virtualenv workflow and only use uv2nix to build packages.
         # This devShell simply adds Python and undoes the dependency leakage done by Nixpkgs Python infrastructure.
         impure = pkgs.mkShell {
-          packages = [
+          packages = with pkgs; [
             python
-            pkgs.uv
+            uv
+            bashInteractive
           ];
           env =
             {