fix: remove double-lambda in mkHome (was rejecting 'sets' argument)

lib/default.nix

@@ -1,11 +1,5 @@
 # lib/default.nix — Entry point for m3ta-home library functions.
 #
-# Provides:
-#   mkHome     — compose a complete HM config from user + identity + context + sets
-#   mkDevShell — create project-level dev shells from language sets
-{inputs}: {
-  mkHome = import ./mkHome.nix {inherit inputs;};
-
-  # TODO: mkDevShell for project-level flake devShells
-  # mkDevShell = import ./mkDevShell.nix { inherit inputs; };
-}
+# Called by flake.nix: import ./lib { inherit inputs; }
+# Re-exports mkHome and future library functions.
+{inputs}: import ./mkHome.nix {inherit inputs;}