Move modules under ./modules

Author: UnstoppableMango

ai/default.nix modules/ai/default.nixai/default.nix renamed to modules/ai/default.nix

@@ -0,0 +1,12 @@
+{
+  imports = [
+    ./ai
+    ./browsers
+    ./desktops
+    ./editors
+    ./gnupg
+    ./shells
+    ./terminals
+    ./toolchain
+  ];
+}