feat(apps-deploy): add direct deployment script

this uses the local machien to build and copies the resulting closure to
the target system. this was necessary for small builders that ran out
of memory building the holochain dependencies.

modules/flake-parts/apps.deploy-/linux.nix

@@ -30,7 +30,41 @@
           inherit (config.config) hostName;
         });
       };
+
+    mkLinuxDeployDirect = {
+      attrName,
+      hostName,
+    }:
+      pkgs.writeShellScript "deploy-direct-${hostName}" ''
+        set -Eeo pipefail
+        export PATH="${lib.makeBinPath (with pkgs; [
+          nix
+          git
+          coreutils
+        ])}:$PATH"
+        set -uxeE -o pipefail
+
+        closure_path=$(nix build --print-out-paths --refresh github:holochain/holochain-infra/deploy/${attrName}#nixosConfigurations.${attrName}.config.system.build.toplevel)
+
+        nix-copy-closure --to root@${hostName} $closure_path
+
+        ssh root@${hostName} "$closure_path/bin/switch-to-configuration ''${1:-switch}"
+      '';
+
+
+    mkLinuxDeployDirectApp = attrName: config:
+      lib.nameValuePair "deploy-direct-${attrName}" {
+        type = "app";
+        program = builtins.toString (mkLinuxDeployDirect {
+          inherit attrName;
+          inherit (config.config) hostName;
+        });
+      };
   in {
-    config.apps = lib.mapAttrs' mkLinuxDeployApp self.nixosConfigurations;
+    config.apps =
+    (lib.mapAttrs' mkLinuxDeployApp self.nixosConfigurations) //
+    (lib.mapAttrs' mkLinuxDeployDirectApp self.nixosConfigurations) //
+    {}
+    ;
   };
 }