feat(direnv): Persist allowed directories

modules/home/users/crumb/direnv.nix

@@ -10,6 +10,14 @@ in {
       enable = true;
       nix-direnv.enable = true;
     };
+
+    # Persist allowed directories.
+    sydnix.impermanence.directories =
+      let xdg-data-home =
+        lib.removePrefix "${config.home.homeDirectory}"
+          (lib.removePrefix "~"
+            config.xdg.dataHome);
+      in [ "${xdg-data-home}/direnv" ];
   };
 }