Add missing dependencies for development environment

In this commit, the missing dependencies for the development environment
have been added to the shell.nix file. The additions include packages
like curl and unzip to ensure that all necessary dependencies are
available for the development environment setup. This modification
enhances the development process by providing the required tools and
libraries.

shell.nix

@@ -1,9 +1,11 @@
 { pkgs ? import <nixpkgs> {} }:
 pkgs.mkShell {
   buildInputs = [
+    pkgs.curl
     pkgs.ghostscript
     pkgs.gnumake
     pkgs.gnused
     pkgs.sqlite
+    pkgs.unzip
   ];
 }