Move from features to option based configuration

modules/home/direnv.nix

@@ -0,0 +1,26 @@
+{ lib
+, pkgs
+, config
+, ...
+}:
+
+with lib; let
+    cfg = config.simmer.direnv;
+in
+{
+    options.simmer.direnv = {
+        enable = mkOption {
+            description = "Whether to install and configure direnv";
+            type = types.bool;
+            default = true;
+        };
+    };
+
+    config = mkIf cfg.enable {
+        programs.direnv = {
+            enable = true;
+            enableBashIntegration = true;
+            nix-direnv.enable = true;
+        };
+    };
+}