feat(attic): update storage config and refine system settings

- Switch disk device from `/dev/vda` to `/dev/sda` for compatibility.
- Add S3 storage configuration with bucket, region, and endpoint.
- Update system state version from `24.05` to `25.11`.
- Remove unused imports and clean up redundant attributes.

systems/x86_64-linux/sgx-attic/default.nix

@@ -1,39 +0,0 @@
-{
-  lib,
-  ...
-}:
-with lib;
-with lib.metacfg;
-{
-  imports = [
-    ./hardware-configuration.nix
-    ./atticd.nix
-  ];
-
-  metacfg = {
-    base.enable = true;
-    nix.enable = true;
-  };
-
-  system.autoUpgrade = {
-    enable = true;
-    operation = "switch";
-    allowReboot = true;
-  };
-
-  virtualisation = {
-    docker.enable = true;
-    podman.dockerCompat = false;
-  };
-
-  security.tpm2.enable = false;
-  security.tpm2.abrmd.enable = false;
-
-  networking.wireless.enable = false; # Enables wireless support via wpa_supplicant.
-  networking.firewall.allowedTCPPorts = [ 8080 ];
-  networking.firewall.allowPing = true;
-
-  powerManagement.cpuFreqGovernor = "ondemand";
-
-  system.stateVersion = "24.05";
-}