Add DMS configuration and helper scripts

- Introduced a new `justfile` for managing DMS-related tasks, including a recipe for syncing live DMS configuration.
- Added a `devshell.nix` file to set up a development environment with necessary packages and shell hooks for DMS.
- Updated DMS settings to replace `defaultSettingsFile` with `defaultSeedDir` for improved configuration management.
- Created a new script `sync-seed.sh` to facilitate syncing DMS settings from the live configuration to host-specific directories.
- Enhanced documentation and examples for DMS configuration and usage.

modules/desktop/shells/dms/default.nix

@@ -38,13 +38,15 @@
         example = [ "sudo" "nixos-rebuild" "switch" "--flake" ".#14900k" ];
         description = "Command used by DMS nix-monitor widget for rebuild actions.";
       };
-      defaultSettingsFile = lib.mkOption {
+      defaultSeedDir = lib.mkOption {
         type = lib.types.nullOr lib.types.path;
         default = null;
-        example = ./dms-default-settings.json;
+        example = ./dms-defaults;
         description = ''
-          Host-specific first-run `settings.json` seed. When set, replaces the bundled
-          `default-settings.nix` template on fresh profiles.
+          Host-specific first-run DMS config seed directory. When set, copies
+          `settings.json` (required) and `plugin_settings.json` (optional) from this
+          directory into `~/.config/DankMaterialShell/` on fresh profiles.
+          Replaces the bundled `default-settings.nix` template for `settings.json`.
         '';
       };
       bundleThirdPartyPlugins = lib.mkOption {
@@ -101,7 +103,6 @@
         ])
         ++ (cfg.extraRightBarWidgets or [ ]);
       programs.nix-monitor.rebuildCommand = rebuildCommand;
-      dms.defaultSettingsFile = cfg.defaultSettingsFile or null;
       dms.bundleThirdPartyPlugins = cfg.bundleThirdPartyPlugins or true;
     };
   };