Split shared host config into dedicated modules

- Add shared modules for boot, hardware, networking, input, and host defaults
- Move host-specific TOML flags to new option namespaces
- Update SSH and service defaults for the new layout

hosts/kled/configuration.nix

@@ -42,12 +42,15 @@
       stateVersion = "25.11";
     };
 
+    boot.secureBoot.enable = true;
+    hardware = {
+      graphics.vaapi = "intel-media-driver";
+      powerSave.enable = true;
+    };
+    input.homeRowMods.enable = true;
+    networking.iwd.enable = true;
+
     config = {
-      laptop.homeRowMods = true;
-      powerSave = true;
-      secureBoot = true;
-      useIwd = true;
-      vaapi = "intel-media-driver";
       locale = "uk_UA.UTF-8";
       timeZone = "Europe/Kyiv";
     };