replace with real hardware configs

nix/hosts/default.nix

@@ -9,8 +9,15 @@ let
       specialArgs = { inherit inputs; };
       modules = [
         ./common.nix
-        ./placeholder-hardware.nix
         inputs.sops-nix.nixosModules.sops
+        inputs.disko.nixosModules.disko
+        # All three boxes are identical qemu guests, so they share one
+        # hardware-configuration.nix and one disko disk layout (single
+        # /dev/sda → GPT → LVM → ext4 root). disko derives fileSystems +
+        # bootloader devices from disk-config.nix. db-host additionally
+        # imports the /dev/sdb data disk from ./db-host.nix.
+        ./hardware-configurations/hardware-configuration.nix
+        ./hardware-configurations/disk-config.nix
         modules.gebos-secrets
         modules.gebos-postgres
         modules.gebos-supabase