adding shell for ags dev

.config/ags/flake.nix

@@ -0,0 +1,25 @@
+
+{
+  description = "The Flake";
+
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { nixpkgs, ... }:
+    {
+      flake-utils.lib.eachDefaultSystem
+        (system:
+          let
+            pkgs = import nixpkgs {
+              inherit system;
+            };
+          in rec
+            {
+              devShell = import ./shell.nix { inherit pkgs; };
+              defaultPackage = pkgs.libsForQt5.callPackage ./default.nix { };
+            }
+        );
+    };
+}