Refactor some modules

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

hosts/common/configs/user/console/ssh-agent/default.nix

@@ -0,0 +1,11 @@
+{
+  user ? throw "user argument is required",
+  home ? throw "home argument is required",
+}:
+{ ... }:
+{
+  home-manager.users.${user} = {
+    services.ssh-agent.enable = true;
+    programs.ssh.addKeysToAgent = "yes";
+  };
+}