fix: add missing non-flake entry

foundation/README.md

@@ -21,7 +21,10 @@ let
         url = "https://github.com/auxolotl/labs/archive/main.tar.gz";
         sha256 = "<sha256>";
     };
-    foundation = import "${labs}/foundation";
+    foundation = import "${labs}/foundation" {
+        # Specifying a system is optional. By default it will use the current system.
+        system = "i686-linux";
+    };
 in
     # ...
 ```

foundation/default.nix

@@ -0,0 +1,14 @@
+{system ? builtins.currentSystem}: let
+  lib = import ./../lib;
+
+  modules = import ./src;
+
+  result = lib.modules.run {
+    modules =
+      (builtins.attrValues modules)
+      ++ [
+        {config.aux.system = system;}
+      ];
+  };
+in
+  result.config.exports.resolved