Refactor desktop home configuration and introduce caching module

- Simplified `desktop-home-base.nix` by removing legacy git and application settings, delegating them to a new `desktop-home-defaults.nix` module for better organization.
- Added a caching configuration for `chiasson.system.caching.attic` in `desktop-home-base.nix`, enabling caching features with customizable options.
- Updated host-specific configurations to remove direct caching settings, ensuring a cleaner and more modular setup.

modules/hosts/uConsole/configuration.nix

@@ -45,16 +45,6 @@
       chiasson.system.librepods.enable = true;
       chiasson.system.palera1n.enable = true;
 
-      # ─────────────────────── Attic (pull + push + CLI token) ────────────────────
-      chiasson.system.caching.attic = {
-        enable = true;
-        cacheName = "nixos-new";
-        endpoint = "http://192.168.2.238:8080/";
-        publicKey = "nixos-new:8NySIcT0HP7KvGQKgBRWoWESxxRA8BVYo8S85UNpNX0=";
-        tokenFile = config.sops.secrets."caching/attic/token".path;
-        push.enable = true;
-        userCli.enable = true;
-      };
       # ─────────────────────── Display Server & Desktop ──────────────────────────
 
       chiasson.desktop = {