modules/system/builder: init remote-builder module

hosts/youko/default.nix

@@ -1,3 +1,17 @@
+{ config, lib, ... }:
+let
+  builderUsers = lib.pipe config.assets.sshKeys.system [
+    (lib.filterAttrs (
+      name: _:
+      !lib.elem name [
+        "youko"
+        "kazuki"
+        "ude"
+      ]
+    ))
+    lib.attrValues
+  ];
+in
 {
   config.systems.nixos.youko.module =
     {
@@ -31,6 +45,11 @@
         settei.desktop.enable = true;
       };
 
+      settei.remote-builder = {
+        enable = true;
+        sshKeys = builderUsers;
+      };
+
       services.udisks2.enable = true;
       settei.incus.enable = true;
       virtualisation.podman.enable = true;